18331328 has 14 divisors (see below), whose sum is σ = 36376356. Its totient is φ = 9165632.

The previous prime is 18331303. The next prime is 18331331. The reversal of 18331328 is 82313381.

It is a self number, because there is not a number n which added to its sum of digits gives 18331328.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 143150 + ... + 143277.

Almost surely, 2^18331328 is an apocalyptic number.

It is an amenable number.

18331328 is a deficient number, since it is larger than the sum of its proper divisors (18045028).

18331328 is an equidigital number, since it uses as much as digits as its factorization.

18331328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286439 (or 286429 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 18331328 is about 4281.5100140021. The cubic root of 18331328 is about 263.6723820929.

The spelling of 18331328 in words is "eighteen million, three hundred thirty-one thousand, three hundred twenty-eight".