131 (number)

← 130 132 → 131
← 130 131 132 133 134 135 136 137 138 139 → List of numbers — Integers ← 100 110 120 130 140 150 160 170 180 190 →
Cardinal	one hundred [and] thirty-one
Ordinal	131st (one hundred [and] thirty-first)
Factorization	prime
Prime	32nd
Roman numeral	CXXXI
Binary	100000112
Octal	2038
Duodecimal	AB12
Hexadecimal	8316

131 is the natural number following 130 and preceding 132.

In mathematics

131 is a Sophie Germain prime, the second 3-digit palindromic prime, and also a permutable prime with 113 and 311. It can be expressed as the sum of three consecutive primes, 131 = 41 + 43 + 47. 131 is an Eisenstein prime with no imaginary part and real part of the form $3n - 1$. Because the next odd number, 133, is a semiprime, 131 is a Chen prime.

131 is a full reptend prime in base 10. The decimal expansion of 1/131 repeats the digits 0076335877862595419847328244274809160305343511450381679389312977099236641221374045801526717557251908396946564885496183206106870229 indefinitely.

In the military

• Convair C-131 Samaritan was an American military transport produced from 1954 to 1956
• USNS Mission Santa Barbara (T-AO-131) was a Buenaventura-class fleet oiler during World War II
• USS Bandera (APA-131) was a is a United States Navy Haskell-class attack transport ship during World War II
• USS Buchanan (DD-131) was a United States Navy Wickes-class destroyer
• USS General T. H. Bliss (AP-131) was a United States Navy General G. O. Squier transport ship during World War II
• USS Hammann (DE-131) was a United States Navy Edsall-class destroyer escort during World War II
• USS Melucta (AK-131) was an United States Navy Crater-class cargo ship during World War II
• USS Walter X. Young (APD-131) was a ship of the United States Navy during World War II
• Strike Fighter Squadron (VFA-131 is a United States Navy F/A-18C Hornet fighter squadron stationed at Naval Air Station Oceana
• ZIL-131 is a 3.5-ton 6x6 army truck

In sports

• The 131st Belmont Stakes was won by Lemon Drop Kid on June 5, 1999
• The 131st Kentucky Derby was won by Giacomo on May 8, 2005

In transportation

• U.S. Route 131 in Michigan
  • M-131 was a former state trunkline designation replaced by U.S. Route 131 and M-119
• Route 131 in Quebec, Canada
• Highway 131 was a former provincial highway in Simcoe County, Ontario
• London Buses route 131 is a Transport for London contracted bus route in London
• The Fiat 131 Mirafiori small/medium family car produced from 1974 to 1984
• STS-131 is a NASA Contingency Logistic Flight (CLF) of the Space Shuttle Atlantis planned for no earlier than February 2010

In other fields

131 is also:

• The year AD131 or 131 BC
• 131 AH is a year in the Islamic calendar that corresponds to 748 – 749 CE.
• 131 Vala is an inner Main belt asteroid
• Iodine-131, or radioiodine, is a radioisotope of iodine for medical and pharmaceutical use
• ACP-131 is the controlling publication for listing of Q codes and Z codes, as published by NATO Allied countries
• Sonnet 131 by William Shakespeare
• Channel 131 on Sirius Satellite Radio is the Fox News Channel
• Channel 131 on XM Radio is BBC World Service
• 131 is the medical emergency telephone number in Chile
• United States Citizenship and Immigration Services Form I-131 to apply for a travel document, reentry permit, refugee travel document or advance parole
• The 131st Westminster Kennel Club Dog Show was won by Ch. Felicity's Diamond Jim, an English Springer Spaniel on February 13, 2007
• In music, the number 131 serves a moniker for Indie music

See also

• List of highways numbered 131
• United Nations Security Council Resolution 131