# 131 (number)

This article may contain indiscriminate, excessive, or irrelevant examples. (April 2016) |

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Cardinal | one hundred thirty-one | |||

Ordinal | 131st (one hundred thirty-first) | |||

Factorization | prime | |||

Prime | 32nd | |||

Divisors | 1, 131 | |||

Greek numeral | ΡΛΑ´ | |||

Roman numeral | CXXXI | |||

Binary | 10000011_{2} | |||

Ternary | 11212_{3} | |||

Quaternary | 2003_{4} | |||

Quinary | 1011_{5} | |||

Senary | 335_{6} | |||

Octal | 203_{8} | |||

Duodecimal | AB_{12} | |||

Hexadecimal | 83_{16} | |||

Vigesimal | 6B_{20} | |||

Base 36 | 3N_{36} |

**131** (**one hundred [and] thirty-one**) is the natural number following 130 and preceding 132.

## Contents

## In mathematics[edit]

**131** is a Sophie Germain prime,^{[1]} an irregular prime,^{[2]} 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 . Because the next odd number, 133, is a semiprime, 131 is a Chen prime. 131 is an Ulam number.^{[3]}

131 is a full reptend prime in base 10 (and also in base 2). The decimal expansion of 1/131 repeats the digits 007633587786259541984732824427480916030534351145038167938931 297709923664122137404580152671755725190839694656488549618320 6106870229 indefinitely.

## In the military[edit]

- Convair C-131 Samaritan was an American military transport produced from 1954 to 1956
- Strike Fighter Squadron (VFA-131) is a United States Navy F/A-18C Hornet fighter squadron stationed at Naval Air Station Oceana
- Tiger 131 is a German Tiger I heavy tank captured in Tunisia by the British 48th Royal Tank Regiment during World War II
- USNS
*Mission Santa Barbara*(T-AO-131) was a*Mission 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*-class 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 a 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 - ZIL-131 is a 3.5-ton 6x6 army truck

## In transportation[edit]

- 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[edit]

**131** is also:

- The year AD 131 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
- 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
- 131 is the ID3v1 tag equivalent to Indie music

## See also[edit]

## References[edit]

**^**"Sloane's A005384 : Sophie Germain primes".*The On-Line Encyclopedia of Integer Sequences*. OEIS Foundation. Retrieved 2016-05-27.**^**"Sloane's A000928 : Irregular primes".*The On-Line Encyclopedia of Integer Sequences*. OEIS Foundation. Retrieved 2016-05-27.**^**"Ulam numbers".*The On-Line Encyclopedia of Integer Sequences*. OEIS Foundation. 2016-04-18. Retrieved 2016-04-19.