Number 18
Number 18 is said 🔊, write in letters as follows: eighteen . Ordinal number 18th is said 🔊 and write: eighteenth. The meaning of number 18: Basic maths, advanced mathematics and properties, computer science, numerology, codes and images, writing and naming in other languages, other interesting facts and comments. Number 18 in News.
Useful information about number 18
The decimal (Arabic) number 18 converted to a Roman number is XVIII.
Roman and decimal number conversions.
18 kilograms (kg) = 39.7 pounds (lb)
18 pounds (lb) = 8.2 kilograms (kg)
18 kilometers (km) equals to 11.185 miles (mi).
18 miles (mi) equals to 28.968 kilometers (km).
18 meters (m) equals to 28.968 feet (ft).
18 feet (ft) equals 5.486 meters (m).
18 centimeters (cm) equals to 7.1 inches (in).
18 inches (in) equals to 45.7 centimeters (cm).
18° Fahrenheit (°F) equals to 64.4° Celsius (°C)
18° Celsius (°C) equals to 7.8° Fahrenheit (°F)
18 Horsepower (hp) equals to 13.24 kilowatts (kW)
18 kilowatts (kW) equals to 24.48 horsepower (hp)
The number 18 converted to a Mayan number is  
Decimal and Mayan number conversions. 
Weight conversion
18 kilograms (kg) = 39.7 pounds (lb)
18 pounds (lb) = 8.2 kilograms (kg)
Length conversion
18 kilometers (km) equals to 11.185 miles (mi).
18 miles (mi) equals to 28.968 kilometers (km).
18 meters (m) equals to 28.968 feet (ft).
18 feet (ft) equals 5.486 meters (m).
18 centimeters (cm) equals to 7.1 inches (in).
18 inches (in) equals to 45.7 centimeters (cm).
Temperature conversion
18° Fahrenheit (°F) equals to 64.4° Celsius (°C)
18° Celsius (°C) equals to 7.8° Fahrenheit (°F)
Power conversion
18 Horsepower (hp) equals to 13.24 kilowatts (kW)
18 kilowatts (kW) equals to 24.48 horsepower (hp)
Codes and images of the number 18
Number 18 morse code: . ..Sign language for number 18:
Images of the number  
Image (1) of the number  Image (2) of the number 
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Number 18 infographic.

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Gregorian, Hebrew, Islamic, Persian and Buddhist year (calendar)
Gregorian year 18 is Buddhist year 561.Buddhist year 18 is Gregorian year 525 a. C.
Gregorian year 18 is Islamic year 623 or 622.
Islamic year 18 is Gregorian year 639 or 640.
Gregorian year 18 is Persian year 605 or 604.
Persian year 18 is Gregorian 639 or 640.
Gregorian year 18 is Hebrew year 3778 or 3779.
Hebrew year 18 is Gregorian year 3742 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. 18
Multiplications
Multiplication table of 18
18 multiplied by two equals 36 (18 x 2 = 36).
18 multiplied by three equals 54 (18 x 3 = 54).
18 multiplied by four equals 72 (18 x 4 = 72).
18 multiplied by five equals 90 (18 x 5 = 90).
show multiplications by 6, 7, 8, 9 ...
Fractions: decimal fraction and common fraction
Fraction table of 18
Half of 18 is 9 (18 / 2 = 9).
One third of 18 is 6 (18 / 3 = 6).
One quarter of 18 is 4,5 (18 / 4 = 4,5 = 4 1/2).
One fifth of 18 is 3,6 (18 / 5 = 3,6 = 3 3/5).
show fractions by 6, 7, 8, 9 ...
Calculator
18  
Advanced math operations
Is Prime?
The number 18 is not a prime number. The closest prime numbers are 17, 19.
18th prime number in order is 61.
Factorization and dividers
Factorization 2 * 3 * 3 = 18
Divisors of number 18 are 1 , 2 , 3 , 6 , 9 , 18
Total Divisors 6.
Sum of Divisors 39.
Powers
The second power of 18^{2} is 324.
The third power of 18^{3} is 5.832.
Roots
The square root √18 is 4,242641.
The cube root of ^{3}√18 is 2,620741.
Logarithms
The natural logarithm of No. ln 18 = log_{e} 18 = 2,890372.
The logarithm to base 10 of No. log_{10} 18 = 1,255273.
The Napierian logarithm of No. log_{1/e} 18 = 2,890372.
Trigonometric functions
The cosine of 18 is 0,660317.The sine of 18 is 0,750987.
The tangent of 18 is 1,137314.
Properties of the number 18
Is a Friedman number: NoIs a Fibonacci number: No
Is a Bell number: No
Is a palindromic number: No
Is a pentagonal number: No
Is a perfect number: No
Number 18 in Computer Science
Code type  Code value 

Port 18/TCP, UDP  Message Send Protocol 
Unix time  Unix time 18 is equal to Thursday Jan. 1, 1970, 12:18 a.m. GMT 
IPv4, IPv6  Number 18 internet address in dotted format v4 0.0.0.18, v6 ::12 
18 Decimal  = 10010 Binary 
18 Decimal  = 200 Ternary 
18 Decimal  = 22 Octal 
18 Decimal  = 12 Hexadecimal (0x12 hex) 
18 BASE64  MTg= 
18 MD5  6f4922f45568161a8cdf4ad2299f6d23 
18 SHA1  9e6a55b6b4563e652a23be9d623ca5055c356940 
More SHA codes related to the number 18 ... 
Numerology 18
The meaning of the number 8 (eight), numerology 8
Character frequency 8: 1
The number eight (8) is the sign of organization, perseverance and control of energy to produce material and spiritual achievements. It represents the power of realization, abundance in the spiritual and material world. Sometimes it denotes a tendency to sacrifice but also to be unscrupulous.
More about the meaning of the number 8 (eight), numerology 8 ...
The meaning of the number 1 (one), numerology 1
Character frequency 1: 1
Number one (1) came to develop or balance creativity, independence, originality, selfreliance and confidence in the world. It reflects power, creative strength, quick mind, drive and ambition. It is the sign of individualistic and aggressive nature.
More about the meaning of the number 1 (one), numerology 1 ...
Interesting facts about the number 18
Asteroids
 (18) Melpomene is asteroid number 18. It was discovered by J. R. Hind from George Bishop Observatory on 6/24/1852.
Areas, mountains and surfaces
 The total area of Iceland (main island) is 39,315 square miles (101,826 square km). Country Iceland. 18th largest island in the world.
Astrology
 It is one of the lucky numbers for the zodiac sign Gemini.
 ¿Qué es la astrología y para qué sirve?
Distances between cities
 There is a 18 miles (28 km) direct distance between Delhi (India) and Farīdābād (India).
 There is a 18 miles (28 km) direct distance between Ecatepec (Mexico) and Iztapalapa (Mexico).
 There is a 18 miles (28 km) direct distance between Klang (Malaysia) and Kuala Lumpur (Malaysia).
 There is a 18 miles (28 km) direct distance between Kobe (Japan) and Sakai (Japan).
 There is a 18 miles (28 km) direct distance between Kowloon (Hong Kong) and Shenzhen (China).
History and politics
 Nazi symbol. 18, which means Adolf Hitler. The number is due to the position of the letters in the Latin alphabet: A = 1 and H = 8. Números del mal.
In other fields
 18 karat gold – 75% pure gold (750 parts per thousand)
Mathematics
 18 is the only positive number that is twice the sum of its digits.
Music
 '18 til I Die ', in Spanish '18 until dying' is a rock song written by Bryan Adams and Robert John 'Mutt' Lange. The song's musical style and production were heavily inspired by rock from the 1980s, and its lyrics are about youth.
 '18 Days ', in Spanish '18 days', is a single by the American rock band 'Saving Abel'.
 '18 Video Tapes ', in Spanish '18 videotapes', is a song by country music artist Jason Meadows.
Science
 Argon is the chemical element in the periodic table that has the symbol Ar and atomic number 18.
Sports
 The best athletes to wear number 18
Peyton Manning, NFL; Dave Cowens, NBA; Charlie Joiner, NFL; Denis Savard, NHL; Bobby Labonte, NASCAR
Please write us
If you know something interesting about the number 18 or any natural number (positive integer), please write to us.Number 18 in other languages
How to say or write the number eighteen in Spanish, German, French and other languages.
Spanish:  🔊 (número 18)  dieciocho 
German:  🔊 (Anzahl 18)  achtzehn 
French:  🔊 (nombre 18)  dixhuit 
Portuguese:  🔊 (número 18)  dezoito 
Chinese:  🔊 (数 18)  十八 
Other languages ... 
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natural number (positive integer).
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Number 18 in News
France24: Man who slapped Macron sentenced to 18 months, 14 suspended A French court on Thursday sentenced a man who slapped French President Emmanuel Macron across the face this week to a prison term of 18 months, 14 of which were suspended. ... June 10, 2021

The Sydney Morning Herald: India to give free vaccines to citizens over 18 in COVID fight Prime Minister Narendra Modi promises to ramp up vaccine procurement to try to vaccinate 75 per cent of Indians sooner than in two years. ... June 8, 2021

BBC: Covid19 vaccine booking opens for everyone over 18 in NI There will be about 20,000 slots available to book weekly, says the Department of Health. ... May 27, 2021

CNN: This man says he has cheated death 18 times CNN affiliate WTVR reports on a man who says he has survived a car crash along with 17 bouts of cancer. ... May 16, 2021

CNN: Rory McIlroy claims first win in 18 months and first as a dad The end of Rory McIlroy's winning drought just so happened to fall on Mother's Day  a fitting way to celebrate with his family. ... May 10, 2021
