256457520 has 120 divisors (see below), whose sum is σ = 939596112. Its totient is φ = 62169600.

The previous prime is 256457507. The next prime is 256457533. The reversal of 256457520 is 25754652.

256457520 is a `hidden beast` number, since 2 + 5 + 64 + 575 + 20 = 666.

256457520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (256457507) and next prime (256457533).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8271 + ... + 24110.

Almost surely, 2^256457520 is an apocalyptic number.

256457520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256457520 is an abundant number, since it is smaller than the sum of its proper divisors (683138592).

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

256457520 is a wasteful number, since it uses less digits than its factorization.

256457520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32411 (or 32402 counting only the distinct ones).

The product of its (nonzero) digits is 84000, while the sum is 36.

The square root of 256457520 is about 16014.2911176237. The cubic root of 256457520 is about 635.3384601099.

The spelling of 256457520 in words is "two hundred fifty-six million, four hundred fifty-seven thousand, five hundred twenty".