256336520 has 64 divisors (see below), whose sum is σ = 649520640. Its totient is φ = 90201600.

The previous prime is 256336519. The next prime is 256336529. The reversal of 256336520 is 25633652.

It is a super-2 number, since 2×256336520² = 131416822971420800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (256336529) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 4244 + ... + 23036.

It is an arithmetic number, because the mean of its divisors is an integer number (10148760).

Almost surely, 2^256336520 is an apocalyptic number.

256336520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256336520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324760320).

256336520 is an abundant number, since it is smaller than the sum of its proper divisors (393184120).

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

256336520 is a wasteful number, since it uses less digits than its factorization.

256336520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18846 (or 18842 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 32.

The square root of 256336520 is about 16010.5127962848. The cubic root of 256336520 is about 635.2385240696.

The spelling of 256336520 in words is "two hundred fifty-six million, three hundred thirty-six thousand, five hundred twenty".