91309717 has 2 divisors, whose sum is σ = 91309718. Its totient is φ = 91309716.

The previous prime is 91309693. The next prime is 91309721. The reversal of 91309717 is 71790319.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88623396 + 2686321 = 9414^2 + 1639^2 .

It is an emirp because it is prime and its reverse (71790319) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91309717 - 2¹¹ = 91307669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91309727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45654858 + 45654859.

It is an arithmetic number, because the mean of its divisors is an integer number (45654859).

Almost surely, 2^91309717 is an apocalyptic number.

It is an amenable number.

91309717 is a deficient number, since it is larger than the sum of its proper divisors (1).

91309717 is an equidigital number, since it uses as much as digits as its factorization.

91309717 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11907, while the sum is 37.

The square root of 91309717 is about 9555.6118066820. The cubic root of 91309717 is about 450.3038556852.

The spelling of 91309717 in words is "ninety-one million, three hundred nine thousand, seven hundred seventeen".