Number 991 facts
The odd number 991 is spelled 🔊, and written in words: nine hundred and ninety-one. The ordinal number 991st is said 🔊 and written as: nine hundred and ninety-first. The meaning of the number 991 in Maths: Is it Prime? Factorization and prime factors tree. The square root and cube root of 991. What is 991 in computer science, numerology, codes and images, photo art, writing and naming in other languages. Other interesting facts, videos related to 991. ‹‹ 990 992 ››
Interesting facts about the number 991

Asteroids
- (991) McDonalda is asteroid number 991. It was discovered by O. Struve from Yerkes Observatory, Williams Bay on 10/24/1922.
Distances
- There is a 991 miles (1,594 km) direct distance between Abū Ghurayb (Iraq) and İstanbul (Turkey).
- There is a 616 miles (991 km) direct distance between Ankara (Turkey) and Yerevan (Armenia).
- There is a 616 miles (991 km) direct distance between Aurangabad (India) and Varanasi (India).
- There is a 616 miles (991 km) direct distance between Baoding (China) and Changchun (China).
- More distances ...
- There is a 616 miles (991 km) direct distance between Baoding (China) and Incheon (South Korea).
- There is a 991 miles (1,594 km) direct distance between Busan (South Korea) and Tainan (Taiwan).
- There is a 991 miles (1,594 km) direct distance between Dubai (United Arab Emirates) and Sanaa (Yemen).
- There is a 991 miles (1,594 km) direct distance between Jinan (China) and Shenzhen (China).
- There is a 616 miles (991 km) direct distance between Ludhiāna (India) and Vadodara (India).
- There is a 616 miles (991 km) direct distance between Pune (India) and Visakhapatnam (India).
- There is a 616 miles (991 km) direct distance between Shivaji Nagar (India) and Visakhapatnam (India).
- There is a 616 miles (991 km) direct distance between Taipei (Taiwan) and Yunfu (China).
- There is a 991 miles (1,594 km) direct distance between Yangon (Burma / Myanmar) and Zhongshan (China).
History and politics
- United Nations Security Council Resolution number 991, adopted 28 April 1995. Terminates the United Nations Observer Mission in El Salvador. Resolution text.
Mathematics
- 991 is the largest three-digit permutable prime
- 991 is a permutable prime.
Motorsport and cars
- Porsche 911 Turbo S 992 v 991 - DRAG RACE
Please write us
If you know something interesting about the number 991 or any natural number (positive integer), please write to us.What is 991 in other units
The number 991 converted to a Mayan number is |
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Decimal and Mayan number conversions. |
Weight conversion
991 kilograms (kg) = 2184.8 pounds (lbs)
991 pounds (lbs) = 449.5 kilograms (kg)
Length conversion
991 kilometers (km) equals to 615.779 miles (mi).
991 miles (mi) equals to 1595 kilometers (km).
991 meters (m) equals to 3252 feet (ft).
991 feet (ft) equals 302.060 meters (m).
991 centimeters (cm) equals to 390.2 inches (in).
991 inches (in) equals to 2517.1 centimeters (cm).
Temperature conversion
991° Fahrenheit (°F) equals to 532.8° Celsius (°C)
991° Celsius (°C) equals to 1815.8° Fahrenheit (°F)
Power conversion
991 Horsepower (hp) equals to 728.78 kilowatts (kW)
991 kilowatts (kW) equals to 1347.57 horsepower (hp)
Time conversion
(hours, minutes, seconds, days, weeks)991 seconds equals to 16 minutes, 31 seconds
991 minutes equals to 16 hours, 31 minutes
Codes and images of the number 991
Number 991 morse code: ----. ----. .----Sign language for number 991:



Number 991 in braille:
Images of the number | |
Image (1) of the number | Image (2) of the number |
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Number 991 infographic![]() |
Gregorian, Hebrew, Islamic, Persian and Buddhist Year (Calendar)
Gregorian year 991 is Buddhist year 1534.Buddhist year 991 is Gregorian year 448 .
Gregorian year 991 is Islamic year 380 or 381.
Islamic year 991 is Gregorian year 1583 or 1584.
Gregorian year 991 is Persian year 369 or 370.
Persian year 991 is Gregorian 1612 or 1613.
Gregorian year 991 is Hebrew year 4751 or 4752.
Hebrew year 991 is Gregorian year 2769 a. C.
More about the year 991.
The Buddhist calendar is used in Sri Lanka, Cambodia, Laos, Thailand, and Burma. The Persian calendar is the official calendar in Iran and Afghanistan.
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Advanced math operations
Is Prime?
The number 991 is a prime number. The closest prime numbers are 983, 997.
The 991st prime number in order is 7841.
Factorization and factors (dividers)
The prime factors of 991
Prime numbers have no prime factors smaller than themselves.
The factors of 991 are 1, 991.
Total factors 2.
Sum of factors 992 (1).
Prime factor tree
991 is a prime number.
Powers
The second power of 9912 is 982.081.
The third power of 9913 is 973.242.271.
Roots
The square root √991 is 31,480152.
The cube root of 3√991 is 9,96991.
Logarithms
The natural logarithm of No. ln 991 = loge 991 = 6,898715.
The logarithm to base 10 of No. log10 991 = 2,996074.
The Napierian logarithm of No. log1/e 991 = -6,898715.
Trigonometric functions
The cosine of 991 is -0,171628.The sine of 991 is -0,985162.
The tangent of 991 is 5,740091.
Number 991 in Computer Science
Code type | Code value |
---|---|
Port 991/TCP, UDP | NAS (Netnews Admin System) |
Html 5 | ϟ SMALL LETTER KOPPA ϟ (UTF-8 Greek and Coptic) |
Unix time | Unix time 991 is equal to Thursday Jan. 1, 1970, 12:16:31 a.m. GMT |
IPv4, IPv6 | Number 991 internet address in dotted format v4 0.0.3.223, v6 ::3df |
991 Decimal | = 1111011111 Binary |
991 Decimal | = 1100201 Ternary |
991 Decimal | = 1737 Octal |
991 Decimal | = 3DF Hexadecimal (0x3df hex) |
991 BASE64 | OTkx |
991 MD5 | 692f93be8c7a41525c0baf2076aecfb4 |
991 SHA1 | e9c535583dbe9b33c317f674d1942accca79f1b3 |
991 SHA224 | b764665aad1ed21ceac6b32b5357d6128a7018bfc52dbc6f7dc2faf5 |
991 SHA256 | 25b7c81e770034aeda70db74af0fb638beca992d2a535641e6313f38b9665016 |
991 SHA384 | 2c7109ba347a729ed11bda9e3d1cbe35ad765d4a5a647ff3c49c0d068b176cd3d970d671f8d96b3b3c2dec908fd19109 |
More SHA codes related to the number 991 ... |
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Numerology 991
More about numerology 991 ...
№ 991 in other languages
Spanish: | 🔊 (número 991) | novecientos noventa y uno |
German: | 🔊 (Nummer 991) | neunhunderteinundneunzig |
French: | 🔊 (nombre 991) | neuf cent quatre-vingt-onze |
Portuguese: | 🔊 (número 991) | novecentos e noventa e um |
Hindi: | 🔊 (संख्या 991) | नौ सौ, इक्यानवे |
Chinese: | 🔊 (数 991) | 九百九十一 |
Arabian: | 🔊 (عدد 991) | تسعمائةواحد و تسعون |
Czech: | 🔊 (číslo 991) | devětset devadesát jedna |
Korean: | 🔊 (번호 991) | 구백구십일 |
Danish: | 🔊 (nummer 991) | nihundrede og enoghalvfems |
Hebrew: | (מספר 991) | תשע מאות תשעים ואחת |
Dutch: | 🔊 (nummer 991) | negenhonderdeenennegentig |
Japanese: | 🔊 (数 991) | 九百九十一 |
Indonesian: | 🔊 (jumlah 991) | sembilan ratus sembilan puluh satu |
Italian: | 🔊 (numero 991) | novecentonovantuno |
Norwegian: | 🔊 (nummer 991) | ni hundre og nitti-en |
Polish: | 🔊 (liczba 991) | dziewięćset dziewięćdzisiąt jeden |
Russian: | 🔊 (номер 991) | девятьсот девяносто один |
Turkish: | 🔊 (numara 991) | dokuzyüzdoksanbir |
Thai: | 🔊 (จำนวน 991) | เก้าร้อยเก้าสิบเอ็ด |
Ukrainian: | 🔊 (номер 991) | дев'ятсот дев'яносто один |
Vietnamese: | 🔊 (con số 991) | chín trăm chín mươi mốt |
Other languages ... |
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Frequently asked questions about the number 991
Is 991 prime and why?
The number 991 is a prime number because its divisors are: 1, 991.
How do you write the number 991 in words?
991 can be written as "nine hundred and ninety-one".