18658664 has 8 divisors (see below), whose sum is σ = 34985010. Its totient is φ = 9329328.

The previous prime is 18658657. The next prime is 18658667. The reversal of 18658664 is 46685681.

It can be written as a sum of positive squares in only one way, i.e., 15665764 + 2992900 = 3958^2 + 1730^2 .

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

It is not an unprimeable number, because it can be changed into a prime (18658667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1166159 + ... + 1166174.

Almost surely, 2^18658664 is an apocalyptic number.

It is an amenable number.

18658664 is a deficient number, since it is larger than the sum of its proper divisors (16326346).

18658664 is a wasteful number, since it uses less digits than its factorization.

18658664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2332339 (or 2332335 counting only the distinct ones).

The product of its digits is 276480, while the sum is 44.

The square root of 18658664 is about 4319.5675709497. The cubic root of 18658664 is about 265.2325666930.

The spelling of 18658664 in words is "eighteen million, six hundred fifty-eight thousand, six hundred sixty-four".