77775664 has 20 divisors (see below), whose sum is σ = 158622040. Its totient is φ = 36840960.

The previous prime is 77775661. The next prime is 77775707. The reversal of 77775664 is 46657777.

It is not an unprimeable number, because it can be changed into a prime (77775661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127617 + ... + 128224.

It is an arithmetic number, because the mean of its divisors is an integer number (7931102).

Almost surely, 2^77775664 is an apocalyptic number.

It is an amenable number.

77775664 is an abundant number, since it is smaller than the sum of its proper divisors (80846376).

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

77775664 is a wasteful number, since it uses less digits than its factorization.

77775664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255868 (or 255862 counting only the distinct ones).

The product of its digits is 1728720, while the sum is 49.

The square root of 77775664 is about 8819.0511961322. The cubic root of 77775664 is about 426.8558546849.

The spelling of 77775664 in words is "seventy-seven million, seven hundred seventy-five thousand, six hundred sixty-four".