256518407715 has 32 divisors (see below), whose sum is σ = 428786049600. Its totient is φ = 130784371200.

The previous prime is 256518407707. The next prime is 256518407723. The reversal of 256518407715 is 517704815652.

256518407715 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (256518407707) and next prime (256518407723).

It is not a de Polignac number, because 256518407715 - 2³ = 256518407707 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2875360 + ... + 2963229.

It is an arithmetic number, because the mean of its divisors is an integer number (13399564050).

Almost surely, 2^256518407715 is an apocalyptic number.

256518407715 is a deficient number, since it is larger than the sum of its proper divisors (172267641885).

256518407715 is a wasteful number, since it uses less digits than its factorization.

256518407715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5838727.

The product of its (nonzero) digits is 2352000, while the sum is 51.

The spelling of 256518407715 in words is "two hundred fifty-six billion, five hundred eighteen million, four hundred seven thousand, seven hundred fifteen".