31857342971 has 2 divisors, whose sum is σ = 31857342972. Its totient is φ = 31857342970.

The previous prime is 31857342961. The next prime is 31857342983. The reversal of 31857342971 is 17924375813.

It is a weak prime.

It is an emirp because it is prime and its reverse (17924375813) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31857342971 is a prime.

It is not a weakly prime, because it can be changed into another prime (31857342961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15928671485 + 15928671486.

It is an arithmetic number, because the mean of its divisors is an integer number (15928671486).

Almost surely, 2^31857342971 is an apocalyptic number.

31857342971 is a deficient number, since it is larger than the sum of its proper divisors (1).

31857342971 is an equidigital number, since it uses as much as digits as its factorization.

31857342971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1270080, while the sum is 50.

The spelling of 31857342971 in words is "thirty-one billion, eight hundred fifty-seven million, three hundred forty-two thousand, nine hundred seventy-one".