256659855120 has 320 divisors, whose sum is σ = 910081751040. Its totient is φ = 66446618112.

The previous prime is 256659855007. The next prime is 256659855139. The reversal of 256659855120 is 21558956652.

It is a happy number.

256659855120 is a `hidden beast` number, since 2 + 5 + 6 + 65 + 9 + 8 + 551 + 20 = 666.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 15502687 + ... + 15519233.

It is an arithmetic number, because the mean of its divisors is an integer number (2844005472).

Almost surely, 2^256659855120 is an apocalyptic number.

256659855120 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 256659855120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455040875520).

256659855120 is an abundant number, since it is smaller than the sum of its proper divisors (653421895920).

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

256659855120 is a wasteful number, since it uses less digits than its factorization.

256659855120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16779 (or 16767 counting only the distinct ones).

The product of its (nonzero) digits is 6480000, while the sum is 54.

The spelling of 256659855120 in words is "two hundred fifty-six billion, six hundred fifty-nine million, eight hundred fifty-five thousand, one hundred twenty".