91567307681 has 2 divisors, whose sum is σ = 91567307682. Its totient is φ = 91567307680.

The previous prime is 91567307593. The next prime is 91567307773. The reversal of 91567307681 is 18670376519.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59187104656 + 32380203025 = 243284^2 + 179945^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91567307681 is a prime.

It is a super-2 number, since 2×91567307681² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91567307081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45783653840 + 45783653841.

It is an arithmetic number, because the mean of its divisors is an integer number (45783653841).

Almost surely, 2^91567307681 is an apocalyptic number.

It is an amenable number.

91567307681 is a deficient number, since it is larger than the sum of its proper divisors (1).

91567307681 is an equidigital number, since it uses as much as digits as its factorization.

91567307681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1905120, while the sum is 53.

The spelling of 91567307681 in words is "ninety-one billion, five hundred sixty-seven million, three hundred seven thousand, six hundred eighty-one".