18172992 has 28 divisors (see below), whose sum is σ = 48083216. Its totient is φ = 6057600.

The previous prime is 18172901. The next prime is 18172993. The reversal of 18172992 is 29927181.

It is a self number, because there is not a number n which added to its sum of digits gives 18172992.

It is not an unprimeable number, because it can be changed into a prime (18172993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47134 + ... + 47517.

Almost surely, 2^18172992 is an apocalyptic number.

18172992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18172992 is an abundant number, since it is smaller than the sum of its proper divisors (29910224).

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

18172992 is an equidigital number, since it uses as much as digits as its factorization.

18172992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94666 (or 94656 counting only the distinct ones).

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

The square root of 18172992 is about 4262.9792399213. The cubic root of 18172992 is about 262.9110331492.

The spelling of 18172992 in words is "eighteen million, one hundred seventy-two thousand, nine hundred ninety-two".