65616664 has 16 divisors (see below), whose sum is σ = 123372000. Its totient is φ = 32717472.

The previous prime is 65616643. The next prime is 65616679. The reversal of 65616664 is 46661656.

It is a congruent number.

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, 8239 + ... + 14110.

It is an arithmetic number, because the mean of its divisors is an integer number (7710750).

Almost surely, 2^65616664 is an apocalyptic number.

It is an amenable number.

65616664 is a deficient number, since it is larger than the sum of its proper divisors (57755336).

65616664 is a wasteful number, since it uses less digits than its factorization.

65616664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22722 (or 22718 counting only the distinct ones).

The product of its digits is 155520, while the sum is 40.

The square root of 65616664 is about 8100.4113475798. The cubic root of 65616664 is about 403.3400820005.

It can be divided in two parts, 6561 and 6664, that added together give a square (13225 = 115²).

The spelling of 65616664 in words is "sixty-five million, six hundred sixteen thousand, six hundred sixty-four".