256537856 has 18 divisors (see below), whose sum is σ = 512074122. Its totient is φ = 128268800.

The previous prime is 256537849. The next prime is 256537859. The reversal of 256537856 is 658735652.

It can be written as a sum of positive squares in only one way, i.e., 256512256 + 25600 = 16016^2 + 160^2 .

It is a super-5 number, since 5×256537856⁵ (a number of 43 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 256537856.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256537859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500795 + ... + 501306.

Almost surely, 2^256537856 is an apocalyptic number.

It is an amenable number.

256537856 is a deficient number, since it is larger than the sum of its proper divisors (255536266).

256537856 is an equidigital number, since it uses as much as digits as its factorization.

256537856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002117 (or 1002103 counting only the distinct ones).

The product of its digits is 1512000, while the sum is 47.

The square root of 256537856 is about 16016.7991808601. The cubic root of 256537856 is about 635.4047936713.

The spelling of 256537856 in words is "two hundred fifty-six million, five hundred thirty-seven thousand, eight hundred fifty-six".