256955138 has 16 divisors (see below), whose sum is σ = 434972160. Its totient is φ = 112770000.

The previous prime is 256955137. The next prime is 256955173. The reversal of 256955138 is 831559652.

It is not an unprimeable number, because it can be changed into a prime (256955131) 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, 200738 + ... + 202013.

It is an arithmetic number, because the mean of its divisors is an integer number (27185760).

Almost surely, 2^256955138 is an apocalyptic number.

256955138 is a deficient number, since it is larger than the sum of its proper divisors (178017022).

256955138 is a wasteful number, since it uses less digits than its factorization.

256955138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402793.

The product of its digits is 324000, while the sum is 44.

The square root of 256955138 is about 16029.8202734778. The cubic root of 256955138 is about 635.7491214797.

The spelling of 256955138 in words is "two hundred fifty-six million, nine hundred fifty-five thousand, one hundred thirty-eight".