256081320 has 96 divisors (see below), whose sum is σ = 907938720. Its totient is φ = 62079360.

The previous prime is 256081283. The next prime is 256081327. The reversal of 256081320 is 23180652.

256081320 is a `hidden beast` number, since 2 + 560 + 81 + 3 + 20 = 666.

It is not an unprimeable number, because it can be changed into a prime (256081327) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28374 + ... + 36293.

It is an arithmetic number, because the mean of its divisors is an integer number (9457695).

Almost surely, 2^256081320 is an apocalyptic number.

256081320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256081320 is an abundant number, since it is smaller than the sum of its proper divisors (651857400).

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

256081320 is a wasteful number, since it uses less digits than its factorization.

256081320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64695 (or 64688 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 256081320 is about 16002.5410482211. The cubic root of 256081320 is about 635.0276467183.

The spelling of 256081320 in words is "two hundred fifty-six million, eighty-one thousand, three hundred twenty".