18638944 has 48 divisors (see below), whose sum is σ = 38041920. Its totient is φ = 8985600.

The previous prime is 18638923. The next prime is 18638957. The reversal of 18638944 is 44983681.

It is a self number, because there is not a number n which added to its sum of digits gives 18638944.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 184494 + ... + 184594.

It is an arithmetic number, because the mean of its divisors is an integer number (792540).

Almost surely, 2^18638944 is an apocalyptic number.

It is an amenable number.

18638944 is an abundant number, since it is smaller than the sum of its proper divisors (19402976).

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

18638944 is a wasteful number, since it uses less digits than its factorization.

18638944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 255 counting only the distinct ones).

The product of its digits is 165888, while the sum is 43.

The square root of 18638944 is about 4317.2843316140. The cubic root of 18638944 is about 265.1390939425.

The spelling of 18638944 in words is "eighteen million, six hundred thirty-eight thousand, nine hundred forty-four".