256791567531 has 32 divisors (see below), whose sum is σ = 362573107200. Its totient is φ = 161397837440.

The previous prime is 256791567499. The next prime is 256791567547. The reversal of 256791567531 is 135765197652.

It is a cyclic number.

It is not a de Polignac number, because 256791567531 - 2⁵ = 256791567499 is a prime.

It is a super-2 number, since 2×256791567531² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (256791567581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1689505 + ... + 1835213.

It is an arithmetic number, because the mean of its divisors is an integer number (11330409600).

Almost surely, 2^256791567531 is an apocalyptic number.

256791567531 is a deficient number, since it is larger than the sum of its proper divisors (105781539669).

256791567531 is a wasteful number, since it uses less digits than its factorization.

256791567531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146219.

The product of its digits is 11907000, while the sum is 57.

The spelling of 256791567531 in words is "two hundred fifty-six billion, seven hundred ninety-one million, five hundred sixty-seven thousand, five hundred thirty-one".