256620 has 96 divisors (see below), whose sum is σ = 903168. Its totient is φ = 52992.

The previous prime is 256609. The next prime is 256639. The reversal of 256620 is 26652.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 256620.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5437 + ... + 5483.

It is an arithmetic number, because the mean of its divisors is an integer number (9408).

2²⁵⁶⁶²⁰ is an apocalyptic number.

256620 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 256620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (451584).

256620 is an abundant number, since it is smaller than the sum of its proper divisors (646548).

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

256620 is a wasteful number, since it uses less digits than its factorization.

256620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 256620 is about 506.5767464067. The cubic root of 256620 is about 63.5472605783.

The spelling of 256620 in words is "two hundred fifty-six thousand, six hundred twenty".