77931808 has 24 divisors (see below), whose sum is σ = 162454572. Its totient is φ = 36673536.

The previous prime is 77931761. The next prime is 77931811. The reversal of 77931808 is 80813977.

It can be written as a sum of positive squares in 2 ways, for example, as 74442384 + 3489424 = 8628^2 + 1868^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71085 + ... + 72172.

Almost surely, 2^77931808 is an apocalyptic number.

It is an amenable number.

77931808 is an abundant number, since it is smaller than the sum of its proper divisors (84522764).

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

77931808 is a wasteful number, since it uses less digits than its factorization.

77931808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143284 (or 143276 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 77931808 is about 8827.8994103920. The cubic root of 77931808 is about 427.1413185586.

The spelling of 77931808 in words is "seventy-seven million, nine hundred thirty-one thousand, eight hundred eight".