91917524977 has 2 divisors, whose sum is σ = 91917524978. Its totient is φ = 91917524976.

The previous prime is 91917524969. The next prime is 91917525017. The reversal of 91917524977 is 77942571919.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74548657296 + 17368867681 = 273036^2 + 131791^2 .

It is a cyclic number.

It is not a de Polignac number, because 91917524977 - 2³ = 91917524969 is a prime.

It is not a weakly prime, because it can be changed into another prime (91917525977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45958762488 + 45958762489.

It is an arithmetic number, because the mean of its divisors is an integer number (45958762489).

Almost surely, 2^91917524977 is an apocalyptic number.

It is an amenable number.

91917524977 is a deficient number, since it is larger than the sum of its proper divisors (1).

91917524977 is an equidigital number, since it uses as much as digits as its factorization.

91917524977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10001880, while the sum is 61.

The spelling of 91917524977 in words is "ninety-one billion, nine hundred seventeen million, five hundred twenty-four thousand, nine hundred seventy-seven".