31518979779 has 8 divisors (see below), whose sum is σ = 48028921600. Its totient is φ = 18010845576.

The previous prime is 31518979771. The next prime is 31518979783. The reversal of 31518979779 is 97797981513.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31518979779 - 2³ = 31518979771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31518979771) 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, 750451879 + ... + 750451920.

It is an arithmetic number, because the mean of its divisors is an integer number (6003615200).

Almost surely, 2^31518979779 is an apocalyptic number.

31518979779 is a deficient number, since it is larger than the sum of its proper divisors (16509941821).

31518979779 is a wasteful number, since it uses less digits than its factorization.

31518979779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1500903809.

The product of its digits is 30005640, while the sum is 66.

The spelling of 31518979779 in words is "thirty-one billion, five hundred eighteen million, nine hundred seventy-nine thousand, seven hundred seventy-nine".