18855172 has 12 divisors (see below), whose sum is σ = 37710400. Its totient is φ = 8080776.

The previous prime is 18855169. The next prime is 18855181. The reversal of 18855172 is 27155881.

18855172 is an admirable number.

It is a super-2 number, since 2×18855172² = 711035022299168, 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, 336672 + ... + 336727.

Almost surely, 2^18855172 is an apocalyptic number.

It is an amenable number.

18855172 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

18855172 is a wasteful number, since it uses less digits than its factorization.

18855172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673410 (or 673408 counting only the distinct ones).

The product of its digits is 22400, while the sum is 37.

The square root of 18855172 is about 4342.2542532652. The cubic root of 18855172 is about 266.1604361258.

The spelling of 18855172 in words is "eighteen million, eight hundred fifty-five thousand, one hundred seventy-two".