256621632 has 56 divisors (see below), whose sum is σ = 690140352. Its totient is φ = 84134400.

The previous prime is 256621577. The next prime is 256621633. The reversal of 256621632 is 236126652.

256621632 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 256621593 and 256621602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256621633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 757 + ... + 22667.

Almost surely, 2^256621632 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256621632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (345070176).

256621632 is an abundant number, since it is smaller than the sum of its proper divisors (433518720).

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

256621632 is a wasteful number, since it uses less digits than its factorization.

256621632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21987 (or 21977 counting only the distinct ones).

The product of its digits is 25920, while the sum is 33.

The square root of 256621632 is about 16019.4142215001. The cubic root of 256621632 is about 635.4739528971.

The spelling of 256621632 in words is "two hundred fifty-six million, six hundred twenty-one thousand, six hundred thirty-two".