18992172 has 24 divisors (see below), whose sum is σ = 46648000. Its totient is φ = 5997456.

The previous prime is 18992161. The next prime is 18992209. The reversal of 18992172 is 27129981.

It is a self number, because there is not a number n which added to its sum of digits gives 18992172.

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, 41422 + ... + 41877.

Almost surely, 2^18992172 is an apocalyptic number.

18992172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18992172 is an abundant number, since it is smaller than the sum of its proper divisors (27655828).

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

18992172 is a wasteful number, since it uses less digits than its factorization.

18992172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83325 (or 83323 counting only the distinct ones).

The product of its digits is 18144, while the sum is 39.

The square root of 18992172 is about 4358.0009178521. Note that the first 3 decimals coincide. The cubic root of 18992172 is about 266.8035137890.

The spelling of 18992172 in words is "eighteen million, nine hundred ninety-two thousand, one hundred seventy-two".