18639436 has 12 divisors (see below), whose sum is σ = 32919040. Its totient is φ = 9234000.

The previous prime is 18639433. The next prime is 18639451. The reversal of 18639436 is 63493681.

It is not an unprimeable number, because it can be changed into a prime (18639433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20940 + ... + 21811.

Almost surely, 2^18639436 is an apocalyptic number.

It is an amenable number.

18639436 is a deficient number, since it is larger than the sum of its proper divisors (14279604).

18639436 is a wasteful number, since it uses less digits than its factorization.

18639436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42864 (or 42862 counting only the distinct ones).

The product of its digits is 93312, while the sum is 40.

The square root of 18639436 is about 4317.3413115018. The cubic root of 18639436 is about 265.1414268230.

The spelling of 18639436 in words is "eighteen million, six hundred thirty-nine thousand, four hundred thirty-six".