130 (number)


130 is the natural number following 129 and preceding 131.

In mathematics

130 is a sphenic number. It is a noncototient since there is no answer to the equation x - Euler's [totient function|φ] = 130.
130 is the only integer that is the sum of the squares of its first four divisors, including 1: 12 + 22 + 52 + 102 = 130.
130 is the largest number that cannot be written as the sum of four hexagonal numbers.
130 equals both 27 + 2 and 53 + 5 and is therefore a doubly strictly number.

In other fields