971911931 has 2 divisors, whose sum is σ = 971911932. Its totient is φ = 971911930.

The previous prime is 971911877. The next prime is 971911937. The reversal of 971911931 is 139119179.

It is a strong prime.

It is an emirp because it is prime and its reverse (139119179) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 971911931 - 2⁶ = 971911867 is a prime.

It is a super-2 number, since 2×971911931² = 1889225603240297522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (971911937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 485955965 + 485955966.

It is an arithmetic number, because the mean of its divisors is an integer number (485955966).

Almost surely, 2^971911931 is an apocalyptic number.

971911931 is a deficient number, since it is larger than the sum of its proper divisors (1).

971911931 is an equidigital number, since it uses as much as digits as its factorization.

971911931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15309, while the sum is 41.

The square root of 971911931 is about 31175.5020969992. The cubic root of 971911931 is about 990.5482563336.

The spelling of 971911931 in words is "nine hundred seventy-one million, nine hundred eleven thousand, nine hundred thirty-one".