256357638 has 24 divisors (see below), whose sum is σ = 556426728. Its totient is φ = 85300992.

The previous prime is 256357547. The next prime is 256357657. The reversal of 256357638 is 836753652.

256357638 is a `hidden beast` number, since 2 + 5 + 6 + 3 + 5 + 7 + 638 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 256357593 and 256357602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1956 + ... + 22727.

It is an arithmetic number, because the mean of its divisors is an integer number (23184447).

Almost surely, 2^256357638 is an apocalyptic number.

256357638 is an abundant number, since it is smaller than the sum of its proper divisors (300069090).

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

256357638 is a wasteful number, since it uses less digits than its factorization.

256357638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25268 (or 25265 counting only the distinct ones).

The product of its digits is 907200, while the sum is 45.

The square root of 256357638 is about 16011.1722868752. The cubic root of 256357638 is about 635.2559680644.

The spelling of 256357638 in words is "two hundred fifty-six million, three hundred fifty-seven thousand, six hundred thirty-eight".