256620320 has 48 divisors (see below), whose sum is σ = 661385088. Its totient is φ = 93315840.

The previous prime is 256620319. The next prime is 256620367. The reversal of 256620320 is 23026652.

It is a self number, because there is not a number n which added to its sum of digits gives 256620320.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71144 + ... + 74663.

It is an arithmetic number, because the mean of its divisors is an integer number (13778856).

Almost surely, 2^256620320 is an apocalyptic number.

256620320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256620320 is an abundant number, since it is smaller than the sum of its proper divisors (404764768).

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

256620320 is a wasteful number, since it uses less digits than its factorization.

256620320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145833 (or 145825 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 256620320 is about 16019.3732711364. The cubic root of 256620320 is about 635.4728699237.

Adding to 256620320 its reverse (23026652), we get a palindrome (279646972).

The spelling of 256620320 in words is "two hundred fifty-six million, six hundred twenty thousand, three hundred twenty".