31197945971 has 2 divisors, whose sum is σ = 31197945972. Its totient is φ = 31197945970.

The previous prime is 31197945953. The next prime is 31197945997. The reversal of 31197945971 is 17954979113.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31197945971 - 2²⁶ = 31130837107 is a prime.

It is not a weakly prime, because it can be changed into another prime (31197945941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15598972985 + 15598972986.

It is an arithmetic number, because the mean of its divisors is an integer number (15598972986).

Almost surely, 2^31197945971 is an apocalyptic number.

31197945971 is a deficient number, since it is larger than the sum of its proper divisors (1).

31197945971 is an equidigital number, since it uses as much as digits as its factorization.

31197945971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2143260, while the sum is 56.

The spelling of 31197945971 in words is "thirty-one billion, one hundred ninety-seven million, nine hundred forty-five thousand, nine hundred seventy-one".