18531772 has 12 divisors (see below), whose sum is σ = 37063600. Its totient is φ = 7942176.

The previous prime is 18531749. The next prime is 18531787. The reversal of 18531772 is 27713581.

18531772 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, 330897 + ... + 330952.

Almost surely, 2^18531772 is an apocalyptic number.

It is an amenable number.

18531772 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.

18531772 is a wasteful number, since it uses less digits than its factorization.

18531772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661860 (or 661858 counting only the distinct ones).

The product of its digits is 11760, while the sum is 34.

The square root of 18531772 is about 4304.8544690849. The cubic root of 18531772 is about 264.6299427150.

The spelling of 18531772 in words is "eighteen million, five hundred thirty-one thousand, seven hundred seventy-two".