256757856 has 24 divisors (see below), whose sum is σ = 673989624. Its totient is φ = 85585920.

The previous prime is 256757819. The next prime is 256757873. The reversal of 256757856 is 658757652.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 256757799 and 256757808.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1337185 + ... + 1337376.

It is an arithmetic number, because the mean of its divisors is an integer number (28082901).

Almost surely, 2^256757856 is an apocalyptic number.

It is an amenable number.

256757856 is an abundant number, since it is smaller than the sum of its proper divisors (417231768).

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

256757856 is a wasteful number, since it uses less digits than its factorization.

256757856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2674574 (or 2674566 counting only the distinct ones).

The product of its digits is 3528000, while the sum is 51.

The square root of 256757856 is about 16023.6654982560. The cubic root of 256757856 is about 635.5863771564.

The spelling of 256757856 in words is "two hundred fifty-six million, seven hundred fifty-seven thousand, eight hundred fifty-six".