Fiftysix

Fifty-six is the natural number that follows fifty-five and precedes fifty-seven. In base-10 notation, it is written as 56.

It is an even composite number with prime factorization 2^3 × 7, and its positive divisors are 1, 2, 4, 7, 8, 14, 28, and 56. In numeral systems, 56 is 111000 in binary and 0x38 in hexadecimal.

The name fifty-six is formed by the words fifty and six, with fifty derived from Old English fiftig. The word reflects the common Germanic-origin practice of combining base words to form the decade and unit.

In science, 56 is the atomic number of barium (Ba). Barium is a soft, pale metal used in X-ray imaging as a contrast agent and in drilling fluids. In computing, DES used a 56-bit key, and contemporary cryptography has moved to longer keys to improve security.

In international dialing, the country code +56 designates Chile. In mathematics, 56 is a pronic number, being the product of consecutive integers 7 and 8, and it is twice the seventh triangular number (2 × 28). Its sum of positive divisors is 120.