31856495779 has 2 divisors, whose sum is σ = 31856495780. Its totient is φ = 31856495778.

The previous prime is 31856495773. The next prime is 31856495791. The reversal of 31856495779 is 97759465813.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31856495779 - 2³ = 31856495771 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31856495779.

It is not a weakly prime, because it can be changed into another prime (31856495771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15928247889 + 15928247890.

It is an arithmetic number, because the mean of its divisors is an integer number (15928247890).

Almost surely, 2^31856495779 is an apocalyptic number.

31856495779 is a deficient number, since it is larger than the sum of its proper divisors (1).

31856495779 is an equidigital number, since it uses as much as digits as its factorization.

31856495779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57153600, while the sum is 64.

The spelling of 31856495779 in words is "thirty-one billion, eight hundred fifty-six million, four hundred ninety-five thousand, seven hundred seventy-nine".