256400653251 has 16 divisors (see below), whose sum is σ = 348058255104. Its totient is φ = 167863075104.

The previous prime is 256400653219. The next prime is 256400653261. The reversal of 256400653251 is 152356004652.

It is not a de Polignac number, because 256400653251 - 2⁵ = 256400653219 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256400653211) 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, 3041416 + ... + 3124581.

It is an arithmetic number, because the mean of its divisors is an integer number (21753640944).

Almost surely, 2^256400653251 is an apocalyptic number.

256400653251 is a deficient number, since it is larger than the sum of its proper divisors (91657601853).

256400653251 is a wasteful number, since it uses less digits than its factorization.

256400653251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6166250.

The product of its (nonzero) digits is 216000, while the sum is 39.

The spelling of 256400653251 in words is "two hundred fifty-six billion, four hundred million, six hundred fifty-three thousand, two hundred fifty-one".