31981003979 has 2 divisors, whose sum is σ = 31981003980. Its totient is φ = 31981003978.

The previous prime is 31981003973. The next prime is 31981004009. The reversal of 31981003979 is 97930018913.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (97930018913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31981003979 - 2²⁸ = 31712568523 is a prime.

It is not a weakly prime, because it can be changed into another prime (31981003973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15990501989 + 15990501990.

It is an arithmetic number, because the mean of its divisors is an integer number (15990501990).

Almost surely, 2^31981003979 is an apocalyptic number.

31981003979 is a deficient number, since it is larger than the sum of its proper divisors (1).

31981003979 is an equidigital number, since it uses as much as digits as its factorization.

31981003979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 367416, while the sum is 50.

The spelling of 31981003979 in words is "thirty-one billion, nine hundred eighty-one million, three thousand, nine hundred seventy-nine".