127 (number)

← 126 127 128 →
← 120 121 122 123 124 125 126 127 128 129 → List of numbers — Integers ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	one hundred and twenty-seven
Ordinal	127th (one hundred and twenty-seventh)
Factorization	prime
Prime	31st
Divisors	1, 127
Roman numeral	CXXVII
Binary	11111112
Ternary	112013
Quaternary	13334
Octal	1778
Duodecimal	A712
Hexadecimal	7F16
Vigesimal	6720
Base 36	3J36

127 (one hundred [and] twenty-seven) is the natural number following 126 and preceding 128.

In mathematics

• As a Mersenne prime, 127 is related to the perfect number 8128. 127 is also an exponent for another Mersenne prime 2¹²⁷ - 1 (2¹²⁷ - 1 was discovered by Édouard Lucas in 1876, and held the record for the largest known prime for 75 years - it is still the largest prime ever discovered by hand calculations). Furthermore, 127 is equal to 2⁷ - 1, and because 7 is also a Mersenne prime, this makes 127 a double Mersenne prime.

• 127 is also a cuban prime of the form $p = (x^3 - y^3) / (x - y)$, $x = y + 1$. The next prime is 131, with which it comprises a cousin prime. Because the next odd number, 129, is a semiprime, 127 is a Chen prime. 127 is greater than the arithmetic mean of its two neighboring primes, thus it is a strong prime.

• 127 is a centered hexagonal number.

• It is the 7th Motzkin number.

• 127 is a palindromic prime in nonary.

• It is the first nice Friedman number in base 10, since 127 = -1 + 2⁷, as well as binary since 1111111 = (1 + 1)¹¹¹ - 1 * 1.

In the military

• USNS Mission San Luis Obispo (T-AO-127) was a Mission Buenaventura Class fleet oilers during World War II
• USS Admiral W. S. Sims (AP-127) was a United States Navy transport ship
• USS Allendale (APA-127) was a United States Navy Haskell-class attack transport ship
• USS Alnitah (AK-127) was a United States Navy Crater-class cargo ship in World War II
• USS Raccoon (IX-127), was a United States Navy Armadillo-class tanker
• USS Tumult (AM-127) was a United States Navy Auk-class minesweeper for removing mines from minefields

In transportation

• The small Fiat 127 automobile
• London Buses route 127 is a Transport for London contracted bus route in London
• 127 is the number of many roads, including U.S. Route 127
• STS-127 was a Space Shuttle Endeavour mission to the International Space Station which launched on June 15, 2009

In other fields

127 is also:

• 127 Hours is a film released in 2010
• The year AD 127 or 127 BC
• 127 AH is a year in the Islamic calendar that corresponds to 744 – 745 CE
• 127 Johanna, a Main belt asteroid
• 127 film, a film format
• The atomic number of Unbiseptium, an element that has not yet been discovered
• The LZ 127 Graf Zeppelin, a dirigible
• Sonnet 127 by William Shakespeare
• 127th Street Ensemble was a troupe of African-American actors which included Tupac Amaru Shakur
• In IP (Internet Protocol) Version 4, it is the last Class A network and is also the subnet used for loopback functionality in computer networking
• The highest signed 8 bit integer
• The non-printable "Delete" (DEL) control character in the ASCII

See also

• 127th (disambiguation)
• List of highways numbered 127
• United Nations Security Council Resolution 127

References

• Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London: Penguin Group. (1987): 136 - 138