56 (fifty-six) is the natural number following 55 and preceding 57.

Cardinal	fifty-six
Ordinal	56th (fifty-sixth)
Factorization
Divisors	2, 4, 7, 8, 14, 28
Roman numeral	LVI
Binary	111000
Hexadecimal	38

In mathematics

56 is the sum of the first six triangular numbers (making it a tetrahedral number), as well as the sum of six consecutive primes (3 + 5 + 7 + 11 + 13 + 17). It is also a tetranacci number and a pronic number.

In science

• The atomic number of barium

In astronomy,

Messier object M56, a magnitude 9.5 globular cluster in the constellation Lyra

The New General Catalogue object NGC 56 , an unverified object in the constellation Pisces . NGC 76 does not appear to be a real object.

The Saros number of the solar eclipse series which began on -1172 July 17 and ended on 144 September 15. The duration of Saros series 56 was 1316.2 years, and it contained 74 solar eclipses.

The Saros number of the lunar eclipse series which began on -852 May 7 and ended on 428 June 13. The duration of Saros series 56 was 1280.1 years, and it contained 72 lunar eclipses.

In other fields

56 is also: .

• The number of men who signed the United States Declaration of Independence.
• The code for international direct dial phone calls to Chile.
• The maximum speed of analog data transmission over a POTS in the 20th century was 56 kbit/s.
• The name of the town Fifty-Six, Arkansas.
• The number of men of Netophah at the Census of men of Israel upon return from exile (Holy Bible, Ezra 2:22).
• The year AD 56, 56 BC, or 1956, and thus the symbol of the anti-Soviet revolution in Hungary.
• In baseball, the number of consecutive games in which Joe DiMaggio had a base hit in 1941, still a record.