91688865 has 32 divisors (see below), whose sum is σ = 153014400. Its totient is φ = 46824960.

The previous prime is 91688843. The next prime is 91688867. The reversal of 91688865 is 56888619.

It is not a de Polignac number, because 91688865 - 2⁸ = 91688609 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91688867) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56181 + ... + 57789.

It is an arithmetic number, because the mean of its divisors is an integer number (4781700).

Almost surely, 2^91688865 is an apocalyptic number.

It is an amenable number.

91688865 is a deficient number, since it is larger than the sum of its proper divisors (61325535).

91688865 is a wasteful number, since it uses less digits than its factorization.

91688865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1777.

The product of its digits is 829440, while the sum is 51.

The square root of 91688865 is about 9575.4302775384. The cubic root of 91688865 is about 450.9262649386.

The spelling of 91688865 in words is "ninety-one million, six hundred eighty-eight thousand, eight hundred sixty-five".