91321519 has 2 divisors, whose sum is σ = 91321520. Its totient is φ = 91321518.

The previous prime is 91321507. The next prime is 91321547. The reversal of 91321519 is 91512319.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91321519 - 2⁵ = 91321487 is a prime.

It is a super-2 number, since 2×91321519² = 16679239664934722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91321589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45660759 + 45660760.

It is an arithmetic number, because the mean of its divisors is an integer number (45660760).

Almost surely, 2^91321519 is an apocalyptic number.

91321519 is a deficient number, since it is larger than the sum of its proper divisors (1).

91321519 is an equidigital number, since it uses as much as digits as its factorization.

91321519 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2430, while the sum is 31.

The square root of 91321519 is about 9556.2293296049. The cubic root of 91321519 is about 450.3232558007.

The spelling of 91321519 in words is "ninety-one million, three hundred twenty-one thousand, five hundred nineteen".