256533621740 has 48 divisors (see below), whose sum is σ = 601362558720. Its totient is φ = 91115532480.

The previous prime is 256533621737. The next prime is 256533621779. The reversal of 256533621740 is 47126335652.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 256533621691 and 256533621700.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13549400 + ... + 13568319.

It is an arithmetic number, because the mean of its divisors is an integer number (12528386640).

Almost surely, 2^256533621740 is an apocalyptic number.

256533621740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256533621740 is an abundant number, since it is smaller than the sum of its proper divisors (344828936980).

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

256533621740 is a wasteful number, since it uses less digits than its factorization.

256533621740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27117782 (or 27117780 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 44.

The spelling of 256533621740 in words is "two hundred fifty-six billion, five hundred thirty-three million, six hundred twenty-one thousand, seven hundred forty".