18638900 has 36 divisors (see below), whose sum is σ = 46226208. Its totient is φ = 6390240.

The previous prime is 18638899. The next prime is 18638911. The reversal of 18638900 is 983681.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12614 + ... + 14013.

Almost surely, 2^18638900 is an apocalyptic number.

18638900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18638900 is an abundant number, since it is smaller than the sum of its proper divisors (27587308).

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

18638900 is a wasteful number, since it uses less digits than its factorization.

18638900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26648 (or 26641 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 18638900 is about 4317.2792358151. The cubic root of 18638900 is about 265.1388853090.

The spelling of 18638900 in words is "eighteen million, six hundred thirty-eight thousand, nine hundred".