970081991 has 2 divisors, whose sum is σ = 970081992. Its totient is φ = 970081990.

The previous prime is 970081979. The next prime is 970082023. The reversal of 970081991 is 199180079.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 970081991 - 2¹⁸ = 969819847 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (970081951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 485040995 + 485040996.

It is an arithmetic number, because the mean of its divisors is an integer number (485040996).

Almost surely, 2^970081991 is an apocalyptic number.

970081991 is a deficient number, since it is larger than the sum of its proper divisors (1).

970081991 is an equidigital number, since it uses as much as digits as its factorization.

970081991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 44.

The square root of 970081991 is about 31146.1392631575. The cubic root of 970081991 is about 989.9261894432.

The spelling of 970081991 in words is "nine hundred seventy million, eighty-one thousand, nine hundred ninety-one".