77

77 (seventy-seven) is the natural number following 76 and preceding 78. Seventy-seven is the smallest positive integer requiring five syllables in English.

← 76 78 → 77
← 70 71 72 73 74 75 76 77 78 79 → List of numbers — Integers 0 10 20 30 40 50 60 70 80 90 →
Cardinal	seventy-seven
Ordinal	77th (seventy-seventh)
Numeral system	77
Factorization
Divisors	1, 7, 11, 77
Roman numeral	LXXVII
Binary	10011012
Octal	1158
Duodecimal	6512
Hexadecimal	4D16

In mathematics

Seventy-seven is the 22nd discrete biprime and the first of the (7.q) family. Since both 7 and 11 are Gaussian primes, this means that 77 is a Blum integer.

It is the sum of three squares, 4² + 5² + 6², as well as the sum of the first eight prime numbers.

77 has an aliquot sum of 19 and it is the second number to do so the first being 65. 77 is the 2nd member of the 19-aliquot tree.

77 and 78 form a Ruth-Aaron pair under the second definition in which repeated prime factors are counted as often as they occur.

It is possible for a sudoku puzzle to have as many as 77 givens yet lack a unique solution.^[1]

77 is an odd number: it can not be divided by two.

77 is a composite number because it has more factors that two (1 and itself).

77 Is not a square number.

In science

• The atomic number of iridium

In astronomy,

Messier object M77, a magnitude 10.5 spiral galaxy in the constellation Cetus

The New General Catalogue object NGC 77, a galaxy in the constellation Cetus

The Saros number of the solar eclipse series which began on -474 July 11 and ended on 788 August 6. The duration of Saros series 77 was 1262.1 years, and it contained 71 solar eclipses.

In history

During World War II in Sweden at the border with Norway, "77" was used as a Shibboleth (password), because the tricky pronunciation in Swedish made it easy to instantly discern whether the speaker was native Swedish, Norwegian, or German.

In religion

In the Islamic tradition, "77" figures prominently. Muhammad is reported to have explained, "Faith has sixty-odd, or seventy-odd branches, the highest and best of which is to declare that there is no god but God, and the lowest of which is to remove something harmful from a road. Shyness, too, is a branch of faith." While some scholars refrain from clarifying "sixty-odd or seventy-odd," various numbers have been suggested, 77 being the most common.^[2] Some have gone so far as to delineate these branches.^[3]

In music

• "77" is often used to denote the year that the punk rock movement rose
• 77 Records label
• Talking Heads' first album, Talking Heads: 77.
• Seminal art-rock Christian band from California, The 77s, headed by iconoclast Michael Roe and founded in 1984. The band is still recording.
• Gibraltarian rock/metal band Breed 77

In sports

• Portland Trail Blazers coach Jack Ramsay led his team to their only NBA title in his first season. #77 was retired in honor of the 1977 NBA title.
• NASCAR driver Travis Kvapil's number in 2005 during his rookie season. This number will return in 2008 driven by Sam Hornish, Jr. sponsored by Mobil 1 and Penske Truck Rental.
• The number posthumously retired by the Minnesota Vikings of the NFL for offensive lineman Korey Stringer.
• The number worn by Ray Bourque in the NHL from 1979-2001. This number has been retired by the Boston Bruins, with whom he played for 20 years, and the Colorado Avalanche, with whom he won the Stanley Cup in his last NHL game.
• The number worn by fellow NHL players Adam Oates, Chris Gratton, Joe Corvo, Paul Coffey, Pierre Turgeon, Ryan Parent and Tom Gilbert.
• The number worn by football legend Red Grange. Retired by both the University of Illinois and the Chicago Bears.
• Alex Melvin of the Pickering Red Sox plays with the number 77.
• NFL Miami Dolphins 2008 1st pick overall out of Michigan LT Jake Long wears #77.
• Number worn by Baltimore Colts offensive line man, Jim Parker. He was the first offensive lineman inducted into the Pro Football Hall of Fame.

In other fields

Seventy-seven is also:

• The year AD 77, 77 BC, or 1977
• 77 Sunset Strip was the address of P.I.s on the TV series of the same name (1958- 64)
• 10-77 - the fire departments' 10 code for high-rise multiple dwelling fire
• 77 WABC (AM), New York City
• The Group of 77 is a group of developing nations at the United Nations.
• The designation of Interstate 77, a freeway that runs from South Carolina to Ohio
• The designation of the M77 motorway in the UK which forms the most northerly part of the A77 trunk road which links Glasgow to Stranraer
• The number of the French department Seine-et-Marne
• Enter 77 is the name of an episode on the television series LOST.

References

1. ^ [1]
2. ^ A Verdict of Mufti Muhammad Hassan
3. ^ Imam al-Tahanawi on the Seventy-Seven Branches