91717649 has 2 divisors, whose sum is σ = 91717650. Its totient is φ = 91717648.

The previous prime is 91717609. The next prime is 91717651. The reversal of 91717649 is 94671719.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79780624 + 11937025 = 8932^2 + 3455^2 .

It is a cyclic number.

It is not a de Polignac number, because 91717649 - 2²⁴ = 74940433 is a prime.

It is a Sophie Germain prime.

Together with 91717651, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (91717609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45858824 + 45858825.

It is an arithmetic number, because the mean of its divisors is an integer number (45858825).

Almost surely, 2^91717649 is an apocalyptic number.

It is an amenable number.

91717649 is a deficient number, since it is larger than the sum of its proper divisors (1).

91717649 is an equidigital number, since it uses as much as digits as its factorization.

91717649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 44.

The square root of 91717649 is about 9576.9331729944. The cubic root of 91717649 is about 450.9734466170.

The spelling of 91717649 in words is "ninety-one million, seven hundred seventeen thousand, six hundred forty-nine".