6315791681 has 2 divisors, whose sum is σ = 6315791682. Its totient is φ = 6315791680.

The previous prime is 6315791623. The next prime is 6315791683. The reversal of 6315791681 is 1861975136.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3362956081 + 2952835600 = 57991^2 + 54340^2 .

It is a cyclic number.

It is not a de Polignac number, because 6315791681 - 2¹⁸ = 6315529537 is a prime.

It is a super-2 number, since 2×6315791681² = 79778449115577611522, which contains 22 as substring.

Together with 6315791683, 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 (6315791683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3157895840 + 3157895841.

It is an arithmetic number, because the mean of its divisors is an integer number (3157895841).

Almost surely, 2^6315791681 is an apocalyptic number.

It is an amenable number.

6315791681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6315791681 is an equidigital number, since it uses as much as digits as its factorization.

6315791681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 272160, while the sum is 47.

The square root of 6315791681 is about 79471.9553112920. The cubic root of 6315791681 is about 1848.4566315708.

The spelling of 6315791681 in words is "six billion, three hundred fifteen million, seven hundred ninety-one thousand, six hundred eighty-one".