18504172 has 6 divisors (see below), whose sum is σ = 32382308. Its totient is φ = 9252084.

The previous prime is 18504169. The next prime is 18504193. The reversal of 18504172 is 27140581.

It is a self number, because there is not a number n which added to its sum of digits gives 18504172.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2313018 + ... + 2313025.

Almost surely, 2^18504172 is an apocalyptic number.

It is an amenable number.

18504172 is a deficient number, since it is larger than the sum of its proper divisors (13878136).

18504172 is a wasteful number, since it uses less digits than its factorization.

18504172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4626047 (or 4626045 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 18504172 is about 4301.6475913306. The cubic root of 18504172 is about 264.4985033083.

The spelling of 18504172 in words is "eighteen million, five hundred four thousand, one hundred seventy-two".