256621724531273 has 16 divisors (see below), whose sum is σ = 272740935220560. Its totient is φ = 240991874323200.

The previous prime is 256621724531243. The next prime is 256621724531311. The reversal of 256621724531273 is 372135427126652.

It can be written as a sum of positive squares in 8 ways, for example, as 3102628599184 + 253519095932089 = 1761428^2 + 15922283^2 .

It is a cyclic number.

It is not a de Polignac number, because 256621724531273 - 2⁶ = 256621724531209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256621724531243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38727218 + ... + 44866923.

It is an arithmetic number, because the mean of its divisors is an integer number (17046308451285).

Almost surely, 2^{256621724531273} is an apocalyptic number.

It is an amenable number.

256621724531273 is a deficient number, since it is larger than the sum of its proper divisors (16119210689287).

256621724531273 is a wasteful number, since it uses less digits than its factorization.

256621724531273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83597068.

The product of its digits is 25401600, while the sum is 56.

The spelling of 256621724531273 in words is "two hundred fifty-six trillion, six hundred twenty-one billion, seven hundred twenty-four million, five hundred thirty-one thousand, two hundred seventy-three".