18609939 has 8 divisors (see below), whose sum is σ = 27570320. Its totient is φ = 12406608.

The previous prime is 18609931. The next prime is 18609973. The reversal of 18609939 is 93990681.

18609939 is a `hidden beast` number, since 1 + 8 + 609 + 9 + 39 = 666.

It is not a de Polignac number, because 18609939 - 2³ = 18609931 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18609894 and 18609903.

It is not an unprimeable number, because it can be changed into a prime (18609931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 344602 + ... + 344655.

It is an arithmetic number, because the mean of its divisors is an integer number (3446290).

Almost surely, 2^18609939 is an apocalyptic number.

18609939 is a deficient number, since it is larger than the sum of its proper divisors (8960381).

18609939 is an equidigital number, since it uses as much as digits as its factorization.

18609939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 689266 (or 689260 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 18609939 is about 4313.9238519010. The cubic root of 18609939 is about 265.0014904390.

The spelling of 18609939 in words is "eighteen million, six hundred nine thousand, nine hundred thirty-nine".