256642992 has 70 divisors (see below), whose sum is σ = 745561532. Its totient is φ = 85543776.

The previous prime is 256642973. The next prime is 256643029. The reversal of 256642992 is 299246652.

256642992 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 663 + ... + 22665.

Almost surely, 2^256642992 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 256642992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (372780766).

256642992 is an abundant number, since it is smaller than the sum of its proper divisors (488918540).

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

256642992 is an equidigital number, since it uses as much as digits as its factorization.

256642992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22029 (or 22008 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The square root of 256642992 is about 16020.0808986721. The cubic root of 256642992 is about 635.4915837140.

The spelling of 256642992 in words is "two hundred fifty-six million, six hundred forty-two thousand, nine hundred ninety-two".