256321516538576 has 20 divisors (see below), whose sum is σ = 496623297549732. Its totient is φ = 128160665558016.

The previous prime is 256321516538513. The next prime is 256321516538587. The reversal of 256321516538576 is 675835615123652.

It can be written as a sum of positive squares in 2 ways, for example, as 112303275960976 + 144018240577600 = 10597324^2 + 12000760^2 .

It is a super-2 number, since 2×256321516538576² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20680010 + ... + 30664406.

Almost surely, 2^{256321516538576} is an apocalyptic number.

It is an amenable number.

256321516538576 is a deficient number, since it is larger than the sum of its proper divisors (240301781011156).

256321516538576 is a wasteful number, since it uses less digits than its factorization.

256321516538576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11588918 (or 11588912 counting only the distinct ones).

The product of its digits is 272160000, while the sum is 65.

The spelling of 256321516538576 in words is "two hundred fifty-six trillion, three hundred twenty-one billion, five hundred sixteen million, five hundred thirty-eight thousand, five hundred seventy-six".