971591081 has 2 divisors, whose sum is σ = 971591082. Its totient is φ = 971591080.

The previous prime is 971591077. The next prime is 971591083. The reversal of 971591081 is 180195179.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 728730025 + 242861056 = 26995^2 + 15584^2 .

It is a cyclic number.

It is not a de Polignac number, because 971591081 - 2² = 971591077 is a prime.

It is a super-2 number, since 2×971591081² = 1887978457357497122, which contains 22 as substring.

Together with 971591083, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (971591083) 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, 485795540 + 485795541.

It is an arithmetic number, because the mean of its divisors is an integer number (485795541).

Almost surely, 2^971591081 is an apocalyptic number.

It is an amenable number.

971591081 is a deficient number, since it is larger than the sum of its proper divisors (1).

971591081 is an equidigital number, since it uses as much as digits as its factorization.

971591081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22680, while the sum is 41.

The square root of 971591081 is about 31170.3558048348. The cubic root of 971591081 is about 990.4392435801.

The spelling of 971591081 in words is "nine hundred seventy-one million, five hundred ninety-one thousand, eighty-one".