255977637128 has 8 divisors (see below), whose sum is σ = 479958069630. Its totient is φ = 127988818560.

The previous prime is 255977637043. The next prime is 255977637137. The reversal of 255977637128 is 821736779552.

It can be written as a sum of positive squares in only one way, i.e., 245462775364 + 10514861764 = 495442^2 + 102542^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15998602313 + ... + 15998602328.

Almost surely, 2^255977637128 is an apocalyptic number.

It is an amenable number.

255977637128 is a deficient number, since it is larger than the sum of its proper divisors (223980432502).

255977637128 is a wasteful number, since it uses less digits than its factorization.

255977637128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31997204647 (or 31997204643 counting only the distinct ones).

The product of its digits is 44452800, while the sum is 62.

The spelling of 255977637128 in words is "two hundred fifty-five billion, nine hundred seventy-seven million, six hundred thirty-seven thousand, one hundred twenty-eight".