18439984 has 20 divisors (see below), whose sum is σ = 35794584. Its totient is φ = 9202688.

The previous prime is 18439979. The next prime is 18440011. The reversal of 18439984 is 48993481.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14544 + ... + 15760.

Almost surely, 2^18439984 is an apocalyptic number.

It is an amenable number.

18439984 is a deficient number, since it is larger than the sum of its proper divisors (17354600).

18439984 is a wasteful number, since it uses less digits than its factorization.

18439984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2172 (or 2166 counting only the distinct ones).

The product of its digits is 248832, while the sum is 46.

The square root of 18439984 is about 4294.1802477306. The cubic root of 18439984 is about 264.1923147230.

The spelling of 18439984 in words is "eighteen million, four hundred thirty-nine thousand, nine hundred eighty-four".