18738920 has 16 divisors (see below), whose sum is σ = 42162660. Its totient is φ = 7495552.

The previous prime is 18738919. The next prime is 18738943. The reversal of 18738920 is 2983781.

It can be written as a sum of positive squares in 2 ways, for example, as 17859076 + 879844 = 4226^2 + 938^2 .

It is a super-2 number, since 2×18738920² = 702294245532800, which contains 22 as substring.

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, 234197 + ... + 234276.

Almost surely, 2^18738920 is an apocalyptic number.

18738920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18738920 is an abundant number, since it is smaller than the sum of its proper divisors (23423740).

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

18738920 is a wasteful number, since it uses less digits than its factorization.

18738920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 468484 (or 468480 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 18738920 is about 4328.8474216586. The cubic root of 18738920 is about 265.6123019535.

The spelling of 18738920 in words is "eighteen million, seven hundred thirty-eight thousand, nine hundred twenty".