18505172 has 12 divisors (see below), whose sum is σ = 37010400. Its totient is φ = 7930776.

The previous prime is 18505159. The next prime is 18505181. The reversal of 18505172 is 27150581.

18505172 is an admirable number.

It is a congruent number.

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 in 3 ways as a sum of consecutive naturals, for example, 330422 + ... + 330477.

It is an arithmetic number, because the mean of its divisors is an integer number (3084200).

Almost surely, 2^18505172 is an apocalyptic number.

It is an amenable number.

18505172 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.

18505172 is a wasteful number, since it uses less digits than its factorization.

18505172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660910 (or 660908 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 29.

The square root of 18505172 is about 4301.7638242935. The cubic root of 18505172 is about 264.5032678868.

The spelling of 18505172 in words is "eighteen million, five hundred five thousand, one hundred seventy-two".