39979931 has 4 divisors (see below), whose sum is σ = 40002864. Its totient is φ = 39957000.

The previous prime is 39979897. The next prime is 39979963. The reversal of 39979931 is 13997993.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 39979931 - 2¹⁸ = 39717787 is a prime.

It is a super-2 number, since 2×39979931² = 3196789765529522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 39979931.

It is not an unprimeable number, because it can be changed into a prime (39979031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8615 + ... + 12416.

It is an arithmetic number, because the mean of its divisors is an integer number (10000716).

Almost surely, 2^39979931 is an apocalyptic number.

39979931 is a deficient number, since it is larger than the sum of its proper divisors (22933).

39979931 is a wasteful number, since it uses less digits than its factorization.

39979931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22932.

The product of its digits is 413343, while the sum is 50.

The square root of 39979931 is about 6322.9685275193. The cubic root of 39979931 is about 341.9379839217.

The spelling of 39979931 in words is "thirty-nine million, nine hundred seventy-nine thousand, nine hundred thirty-one".