17979939 has 6 divisors (see below), whose sum is σ = 25971036. Its totient is φ = 11986620.

The previous prime is 17979937. The next prime is 17980009. The reversal of 17979939 is 93997971.

It is not a de Polignac number, because 17979939 - 2¹ = 17979937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (17979937) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 998877 + ... + 998894.

It is an arithmetic number, because the mean of its divisors is an integer number (4328506).

Almost surely, 2^17979939 is an apocalyptic number.

17979939 is a deficient number, since it is larger than the sum of its proper divisors (7991097).

17979939 is a wasteful number, since it uses less digits than its factorization.

17979939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1997777 (or 1997774 counting only the distinct ones).

The product of its digits is 964467, while the sum is 54.

The square root of 17979939 is about 4240.2758165006. The cubic root of 17979939 is about 261.9767426862.

The spelling of 17979939 in words is "seventeen million, nine hundred seventy-nine thousand, nine hundred thirty-nine".