91909373 has 2 divisors, whose sum is σ = 91909374. Its totient is φ = 91909372.

The previous prime is 91909351. The next prime is 91909387. The reversal of 91909373 is 37390919.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51294244 + 40615129 = 7162^2 + 6373^2 .

It is a cyclic number.

It is not a de Polignac number, because 91909373 - 2²⁴ = 75132157 is a prime.

It is a super-3 number, since 3×91909373³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91909373.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91909333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45954686 + 45954687.

It is an arithmetic number, because the mean of its divisors is an integer number (45954687).

Almost surely, 2^91909373 is an apocalyptic number.

It is an amenable number.

91909373 is a deficient number, since it is larger than the sum of its proper divisors (1).

91909373 is an equidigital number, since it uses as much as digits as its factorization.

91909373 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45927, while the sum is 41.

The square root of 91909373 is about 9586.9376236627. The cubic root of 91909373 is about 451.2874619953.

The spelling of 91909373 in words is "ninety-one million, nine hundred nine thousand, three hundred seventy-three".