53 (number)

53 is the natural number following 52 and preceding 54.

List of numbers — Integers << 50 51 52 53 54 55 56 57 58 59 >>
Cardinal	fifty-three
Ordinal	53rd (fiftieth)
Factorization	prime
Roman numeral	LIII
Binary	110101
Hexadecimal	35

In mathematics

Fifty-three is the 16th smallest prime number. The next is fifty-nine. Fifty-three is also a Sophie Germain prime, and the sum of five consecutive primes (5 + 7 + 11 + 13 + 17). But 53 can not be expressed as the sum of any integer and its base 10 digits, making 53 a self number.

53 written in hexadecimal is 35, that is, the same characters used in the decimal representation, but reversed. Three multiples of 53 share this property: 371 = 173₁₆, 5141 = 1415₁₆, 99481 = 14899₁₆.

In other fields

Fifty-three is also:

• The atomic number of iodine.
• The code for international direct dial phone calls to Cuba.
• In the title of the 1912 movie North of Fifty Three, remade in 1917.
• The number of short poems in the book Rumi Birdsong by Jelaluddin Rumi.
• The year AD 53, 53 BC, and 1953.