91688319 has 12 divisors (see below), whose sum is σ = 139409400. Its totient is φ = 57908304.

The previous prime is 91688309. The next prime is 91688323. The reversal of 91688319 is 91388619.

It is a de Polignac number, because none of the positive numbers 2^k-91688319 is a prime.

It is a super-2 number, since 2×91688319² = 16813495682091522, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91688309) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 267924 + ... + 268265.

It is an arithmetic number, because the mean of its divisors is an integer number (11617450).

Almost surely, 2^91688319 is an apocalyptic number.

91688319 is a deficient number, since it is larger than the sum of its proper divisors (47721081).

91688319 is a wasteful number, since it uses less digits than its factorization.

91688319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536214 (or 536211 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 91688319 is about 9575.4017670278. The cubic root of 91688319 is about 450.9253698600.

The spelling of 91688319 in words is "ninety-one million, six hundred eighty-eight thousand, three hundred nineteen".