18807939 has 12 divisors (see below), whose sum is σ = 27540136. Its totient is φ = 12366432.

The previous prime is 18807931. The next prime is 18807973. The reversal of 18807939 is 93970881.

It is not a de Polignac number, because 18807939 - 2³ = 18807931 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18807894 and 18807903.

It is not an unprimeable number, because it can be changed into a prime (18807931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13657 + ... + 14970.

Almost surely, 2^18807939 is an apocalyptic number.

18807939 is a deficient number, since it is larger than the sum of its proper divisors (8732197).

18807939 is a wasteful number, since it uses less digits than its factorization.

18807939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28706 (or 28703 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 18807939 is about 4336.8120780131. The cubic root of 18807939 is about 265.9380025863.

The spelling of 18807939 in words is "eighteen million, eight hundred seven thousand, nine hundred thirty-nine".