65657664 has 42 divisors (see below), whose sum is σ = 188197490. Its totient is φ = 21885696.

The previous prime is 65657639. The next prime is 65657671. The reversal of 65657664 is 46675656.

It can be written as a sum of positive squares in only one way, i.e., 64641600 + 1016064 = 8040^2 + 1008^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 56419 + ... + 57570.

Almost surely, 2^65657664 is an apocalyptic number.

65657664 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

65657664 is an abundant number, since it is smaller than the sum of its proper divisors (122539826).

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

65657664 is a wasteful number, since it uses less digits than its factorization.

65657664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114007 (or 113994 counting only the distinct ones).

The product of its digits is 907200, while the sum is 45.

The square root of 65657664 is about 8102.9416880538. The cubic root of 65657664 is about 403.4240723531.

The spelling of 65657664 in words is "sixty-five million, six hundred fifty-seven thousand, six hundred sixty-four".