256402640351 has 64 divisors (see below), whose sum is σ = 310224950784. Its totient is φ = 208838822400.

The previous prime is 256402640339. The next prime is 256402640357. The reversal of 256402640351 is 153046204652.

It is not a de Polignac number, because 256402640351 - 2³⁴ = 239222771167 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256402640357) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 371059916 + ... + 371060606.

It is an arithmetic number, because the mean of its divisors is an integer number (4847264856).

Almost surely, 2^256402640351 is an apocalyptic number.

256402640351 is a deficient number, since it is larger than the sum of its proper divisors (53822310433).

256402640351 is a wasteful number, since it uses less digits than its factorization.

256402640351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1224.

The product of its (nonzero) digits is 172800, while the sum is 38.

The spelling of 256402640351 in words is "two hundred fifty-six billion, four hundred two million, six hundred forty thousand, three hundred fifty-one".