31719857979 has 8 divisors (see below), whose sum is σ = 42319867392. Its totient is φ = 21133210280.

The previous prime is 31719857941. The next prime is 31719857989. The reversal of 31719857979 is 97975891713.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 31719857979 - 2⁸ = 31719857723 is a prime.

It is a super-2 number, since 2×31719857979² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31719857989) 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, 3334887 + ... + 3344384.

It is an arithmetic number, because the mean of its divisors is an integer number (5289983424).

Almost surely, 2^31719857979 is an apocalyptic number.

31719857979 is a deficient number, since it is larger than the sum of its proper divisors (10600009413).

31719857979 is a wasteful number, since it uses less digits than its factorization.

31719857979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6680857.

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

The spelling of 31719857979 in words is "thirty-one billion, seven hundred nineteen million, eight hundred fifty-seven thousand, nine hundred seventy-nine".