18311912 has 16 divisors (see below), whose sum is σ = 35172900. Its totient is φ = 8932480.

The previous prime is 18311893. The next prime is 18311947. The reversal of 18311912 is 21911381.

18311912 = 594² + 595² + ... + 641².

It can be written as a sum of positive squares in 2 ways, for example, as 16532356 + 1779556 = 4066^2 + 1334^2 .

It is a super-2 number, since 2×18311912² = 670652242191488, which contains 22 as substring.

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, 27587 + ... + 28242.

Almost surely, 2^18311912 is an apocalyptic number.

It is an amenable number.

18311912 is a deficient number, since it is larger than the sum of its proper divisors (16860988).

18311912 is a wasteful number, since it uses less digits than its factorization.

18311912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55876 (or 55872 counting only the distinct ones).

The product of its digits is 432, while the sum is 26.

The square root of 18311912 is about 4279.2419889508. The cubic root of 18311912 is about 263.5792578796.

The spelling of 18311912 in words is "eighteen million, three hundred eleven thousand, nine hundred twelve".