18664385 has 16 divisors (see below), whose sum is σ = 24748416. Its totient is φ = 13440768.

The previous prime is 18664367. The next prime is 18664411. The reversal of 18664385 is 58346681.

It is a cyclic number.

It is not a de Polignac number, because 18664385 - 2²⁰ = 17615809 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2819 + ... + 6728.

It is an arithmetic number, because the mean of its divisors is an integer number (1546776).

Almost surely, 2^18664385 is an apocalyptic number.

It is an amenable number.

18664385 is a deficient number, since it is larger than the sum of its proper divisors (6084031).

18664385 is a wasteful number, since it uses less digits than its factorization.

18664385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9592.

The product of its digits is 138240, while the sum is 41.

The square root of 18664385 is about 4320.2297392616. The cubic root of 18664385 is about 265.2596718929.

The spelling of 18664385 in words is "eighteen million, six hundred sixty-four thousand, three hundred eighty-five".