256681038864 has 80 divisors (see below), whose sum is σ = 696567024000. Its totient is φ = 81291015168.

The previous prime is 256681038839. The next prime is 256681038883. The reversal of 256681038864 is 468830186652.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 615709 + ... + 944700.

It is an arithmetic number, because the mean of its divisors is an integer number (8707087800).

Almost surely, 2^256681038864 is an apocalyptic number.

256681038864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

256681038864 is an abundant number, since it is smaller than the sum of its proper divisors (439885985136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256681038864 is a wasteful number, since it uses less digits than its factorization.

256681038864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1560592 (or 1560586 counting only the distinct ones).

The product of its (nonzero) digits is 13271040, while the sum is 57.

The spelling of 256681038864 in words is "two hundred fifty-six billion, six hundred eighty-one million, thirty-eight thousand, eight hundred sixty-four".