255617856978 has 16 divisors (see below), whose sum is σ = 557711688096. Its totient is φ = 77459956640.

The previous prime is 255617856953. The next prime is 255617856979. The reversal of 255617856978 is 879658716552.

It is not an unprimeable number, because it can be changed into a prime (255617856979) 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, 1936498851 + ... + 1936498982.

It is an arithmetic number, because the mean of its divisors is an integer number (34856980506).

Almost surely, 2^255617856978 is an apocalyptic number.

255617856978 is an abundant number, since it is smaller than the sum of its proper divisors (302093831118).

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

255617856978 is a wasteful number, since it uses less digits than its factorization.

255617856978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3872997849.

The product of its digits is 254016000, while the sum is 69.

The spelling of 255617856978 in words is "two hundred fifty-five billion, six hundred seventeen million, eight hundred fifty-six thousand, nine hundred seventy-eight".