Number 21
Number 21 spell 🔊, write in words: twenty-one . Ordinal number 21th is said 🔊 and write: twenty-first. The meaning of number 21 in Maths: Is Prime? Factorization and prime factors tree. The square root and cube root of 21. What is 21 in computer science, numerology, codes and images, writing and naming in other languages. Other interesting facts, videos, news related to 21.
What is 21 in other units
The number 21 converted to a Mayan number is | |
Decimal and Mayan number conversions. |
Weight conversion
21 kilograms (kg) = 46.3 pounds (lbs)
21 pounds (lbs) = 9.5 kilograms (kg)
Length conversion
21 kilometers (km) equals to 13.049 miles (mi).
21 miles (mi) equals to 33.796 kilometers (km).
21 meters (m) equals to 33.796 feet (ft).
21 feet (ft) equals 6.401 meters (m).
21 centimeters (cm) equals to 8.3 inches (in).
21 inches (in) equals to 53.3 centimeters (cm).
Temperature conversion
21° Fahrenheit (°F) equals to -6.1° Celsius (°C)
21° Celsius (°C) equals to 69.8° Fahrenheit (°F)
Power conversion
21 Horsepower (hp) equals to 15.44 kilowatts (kW)
21 kilowatts (kW) equals to 28.56 horsepower (hp)
Codes and images of the number 21
Number 21 morse code: ..--- .----Sign language for number 21:
Number 21 in braille:
Images of the number | |
Image (1) of the number | Image (2) of the number |
More images, other sizes, codes and colors ... | |
Number 21 infographic |
Year 21 AD
Gregorian, Hebrew, Islamic, Persian and Buddhist year (calendar)
Gregorian year 21 is Buddhist year 564.Buddhist year 21 is Gregorian year 522 a. C.
Gregorian year 21 is Islamic year -620 or -618.
Islamic year 21 is Gregorian year 641 or 642.
Gregorian year 21 is Persian year -602 or -601.
Persian year 21 is Gregorian 642 or 643.
Gregorian year 21 is Hebrew year 3781 or 3782.
Hebrew year 21 is Gregorian year 3739 a. C.
The Buddhist calendar is used in Sri Lanka, Cambodia, Laos, Thailand, and Burma. The Persian calendar is official in Iran and Afghanistan.
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Mathematics of no. 21
Multiplications
Multiplication table of 21
21 multiplied by two equals 42 (21 x 2 = 42).
21 multiplied by three equals 63 (21 x 3 = 63).
21 multiplied by four equals 84 (21 x 4 = 84).
21 multiplied by five equals 105 (21 x 5 = 105).
21 multiplied by seven equals 147 (21 x 7 = 147).
21 multiplied by eight equals 168 (21 x 8 = 168).
21 multiplied by nine equals 189 (21 x 9 = 189).
Fractions: decimal fraction and common fraction
Fraction table of 21
Half of 21 is 10,5 (21 / 2 = 10,5 = 10 1/2).
One third of 21 is 7 (21 / 3 = 7).
One quarter of 21 is 5,25 (21 / 4 = 5,25 = 5 1/4).
One fifth of 21 is 4,2 (21 / 5 = 4,2 = 4 1/5).
One seventh of 21 is 3 (21 / 7 = 3).
One eighth of 21 is 2,625 (21 / 8 = 2,625 = 2 5/8).
One ninth of 21 is 2,3333 (21 / 9 = 2,3333 = 2 1/3).
Calculator
21 | ||||
Advanced math operations
Is Prime?
The number 21 is not a prime number. The closest prime numbers are 19, 23.
21th prime number in order is 73.
Factorization and factors (dividers)
The prime factors of 21 are 3 * 7
The factors of 21 are 1 , 3 , 7 , 21
Total factors 4.
Sum of factors 32 (11).
Prime factor tree
Powers
The second power of 21^{2} is 441.
The third power of 21^{3} is 9.261.
Roots
The square root √21 is 4,582576.
The cube root of ^{3}√21 is 2,758924.
Logarithms
The natural logarithm of No. ln 21 = log_{e} 21 = 3,044522.
The logarithm to base 10 of No. log_{10} 21 = 1,322219.
The Napierian logarithm of No. log_{1/e} 21 = -3,044522.
Trigonometric functions
The cosine of 21 is -0,547729.The sine of 21 is 0,836656.
The tangent of 21 is -1,527499.
Number 21 in Computer Science
Code type | Code value |
---|---|
Port 21/TCP | FTP Protocol (control) - port for FTP commands and flow control |
Unix time | Unix time 21 is equal to Thursday Jan. 1, 1970, 12:21 a.m. GMT |
IPv4, IPv6 | Number 21 internet address in dotted format v4 0.0.0.21, v6 ::15 |
21 Decimal | = 10101 Binary |
21 Decimal | = 210 Ternary |
21 Decimal | = 25 Octal |
21 Decimal | = 15 Hexadecimal (0x15 hex) |
21 BASE64 | MjE= |
21 MD5 | 3c59dc048e8850243be8079a5c74d079 |
21 SHA1 | 472b07b9fcf2c2451e8781e944bf5f77cd8457c8 |
21 SHA224 | 112a6cfa3ed398a5248c479ed6a061d397633a3fb4d5b9ecca274695 |
21 SHA256 | 6f4b6612125fb3a0daecd2799dfd6c9c299424fd920f9b308110a2c1fbd8f443 |
21 SHA384 | 395809b7b4da42f70785d72cc237e64c7916fa6b2167c15202c09915071639718369426689502bd6a7b60e24cd90d8e8 |
More SHA codes related to the number 21 ... |
If you know something interesting about the 21 number that you did not find on this page, do not hesitate to write us here.
Numerology 21
The meaning of the number 2 (two), numerology 2
Character frequency 2: 1
The number 2 (two) is also the symbol of balance, togetherness and receptivity. He/she is a good partner, colleague or companion; he/she also plays a wonderful role as a referee or mediator. Number 2 person is modest, sincere, spiritually influenced and a good diplomat. It represents intuition and vulnerability.
The meaning of the number 1 (one), numerology 1
Character frequency 1: 1
Interesting facts about the number 21
Asteroids
- (21) Lutetia is asteroid number 21. It was discovered by H. M. S. Goldschmidt from Paris on 11/15/1852.
Aircrafts and flights
- 07/08/1965 the Canadian Pacific Air Lines plane, flight number 21, Douglas DC-6B crashed in near 100 Mile House, BC, Canada 46 passengers and 6 crew members died.
Areas, mountains and surfaces
- The total area of Hokkaido is 30,394 square miles (78,719 square km). Country Japan (Hokkaido region). 21th largest island in the world.
- The total area of Nauru is 8.1 square miles (21 km²)
Astrology
- It is one of the lucky numbers for the zodiac sign Aries and Scorpio.
- What is astrology and what is it for?
Distances between cities
- There is a 14 miles (21 km) direct distance between Bogor (Indonesia) and Depok (Indonesia).
- There is a 14 miles (21 km) direct distance between Dombivli (India) and Navi Mumbai (India).
- There is a 14 miles (21 km) direct distance between Ecatepec (Mexico) and Mexico City (Mexico).
Games
- Pokémon Spearow (Onisuzume) is a Pokémon number # 021 of the National Pokédex. Spearow is a normal, flying type Pokémon in the first generation. It is a Flying Egg group Pokémon. Spearow's other indexes are Kalos Centro index 109 - Highland Pokédex, Johto index 013 .
- 21 is a player's highest score in a hand of Blackjack or Twenty-one.
History and politics
- United Nations Security Council Resolution number 21, adopted 2 April 1947. Trusteeship of strategic areas: German Pacific Islands. Resolution text.
In other fields
- Dreaming of the number 21 means transmuting all of the above for spiritual balance, if this number repeats itself in time it is a good sign that you are achieving it.
Mathematics
- 21 is the number of spots on a standard cubical die (1+2+3+4+5+6)
- 21 is the first century with ten prime years
- 21 is the smallest number of distinct squares needed to tile a square.
Music
- '21 Seconds' is a song from the acronym of the British garage So Solid Crew.
- '21 Questions ', in Spanish '21 questions', is a song performed by 50 Cent, an American rapper and businessman.
- '21' is the debut single from The Paddingtons. '21' is also a song recorded by American singer Hunter Hayes.
- '21 Guns ', in Spanish '21 armas de fuego', is a song by the American punk rock band Green Day.
- '21 (Moon Water) 'is a song by the North American indie band Bon Iver.
- '21 Summer ', in Spanish '21 Verano', is a song by the American country music duo Brothers Osborne.
- More music ...
- '21 Savage 'is an American rapper, singer and songwriter. His name is Shyjah Joseph (Decatur, Georgia, October 22, 1992).
Science
- Scandium is the chemical element in the periodic table that has the symbol Sc and atomic number 21.
Sports
- The best athletes to wear number 21
Roberto Clemente, MLB; Tim Duncan, NBA; Warren Spahn, MLB; LaDainian Tomlinson, NFL; Sammy Sosa, MLB; David Pearson, NASCAR; Roger Clemens, MLB; Deion Sanders, NFL
Tv, movies and cinematography
- 21 trailer
- Movie: 21 Days Together Year: 1940 Runtime: 72 Director: Basil Dean With: Vivien Leigh; Leslie banks
- Film: 21 Grams (21 Grams) Year: 2003 Duration: 125 Director: Alejandro González Inárritu With: Sean Penn; Benicio, the bull
- Film: '21 blackjack '(English title: 21) is a 2008 film directed by Robert Luketic and starring Jim Sturgess, Kevin Spacey, Kate Bosworth and Laurence Fishburne.
Please write us
If you know something interesting about the number 21 or any natural number (positive integer), please write to us.№ 21 in other languages
Spanish: | 🔊 (número 21) | veintiuno |
German: | 🔊 (Nummer 21) | einundzwanzig |
French: | 🔊 (nombre 21) | vingt et un |
Portuguese: | 🔊 (número 21) | vinte e um |
Hindi: | 🔊 (संख्या 21) | इक्कीस |
Chinese: | 🔊 (数 21) | 二十一 |
Arabian: | 🔊 (عدد 21) | واحد و عشرون |
Czech: | 🔊 (číslo 21) | dvacet jedna |
Korean: | 🔊 (번호 21) | 이십일 |
Danish: | 🔊 (nummer 21) | enogtyve |
Hebrew: | (מספר 21) | עשרים ואחד |
Dutch: | 🔊 (nummer 21) | eenentwintig |
Japanese: | 🔊 (数 21) | 二十一 |
Indonesian: | 🔊 (jumlah 21) | dua puluh satu |
Italian: | 🔊 (numero 21) | ventiuno |
Norwegian: | 🔊 (nummer 21) | tjue-en |
Polish: | 🔊 (liczba 21) | dwadzieścia jeden |
Russian: | 🔊 (номер 21) | двадцать один |
Turkish: | 🔊 (numara 21) | yirmibir |
Thai: | 🔊 (จำนวน 21) | ยี่สิบเอ็ด |
Ukrainian: | 🔊 (номер 21) | двадцять одна |
Vietnamese: | 🔊 (con số 21) | hai mươi mốt |
Other languages ... |
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Number 21 in News
BBC: Tony Hickmott: Autistic man to be released after 21 years in hospital
Mum of Tony Hickmott, who has been held in a secure hospital since 2001, says: "He's coming home." ... Oct. 4, 2022 |
BBC: One-Day Cup: Kent end losing streak in finals to beat Lancs by 21 runs at Trent Bridge
Kent win their first List A trophy since 1978 as they beat Lancashire by 21 runs at Trent Bridge to win the One-Day Cup. Sept. 17, 2022 |
The Sydney Morning Herald: At least 21 killed in Somalia hotel siege, many hostages freed
Elite armed forces battled al Qaeda-linked militants for 30 hours after the jihadists blasted and shot their way into the Hayat Hotel. Aug. 22, 2022 |
NyTimes: Somali Hotel Siege Ends With 21 People Dead
Officials said that 117 others had been wounded in the 30-hour siege by Shabab militants at an upscale hotel in Somalia’s capital. Aug. 21, 2022 |
France24: Suspected jihadists kill at least 21 in north Mali attack
At least 17 soldiers and four civilians were killed Sunday in an attack in a strategic border zone between Mali, Burkina Faso and Niger, Mali’s army said. Aug. 8, 2022 |