256578140 has 48 divisors (see below), whose sum is σ = 663160512. Its totient is φ = 81202176.

The previous prime is 256578089. The next prime is 256578181. The reversal of 256578140 is 41875652.

256578140 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 = 256578094 and 256578103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68669 + ... + 72308.

It is an arithmetic number, because the mean of its divisors is an integer number (13815844).

Almost surely, 2^256578140 is an apocalyptic number.

256578140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256578140 is an abundant number, since it is smaller than the sum of its proper divisors (406582372).

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

256578140 is a wasteful number, since it uses less digits than its factorization.

256578140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141006 (or 141004 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 38.

The square root of 256578140 is about 16018.0566861277. The cubic root of 256578140 is about 635.4380510203.

The spelling of 256578140 in words is "two hundred fifty-six million, five hundred seventy-eight thousand, one hundred forty".