91691678 has 16 divisors (see below), whose sum is σ = 153226080. Its totient is φ = 40859616.

The previous prime is 91691657. The next prime is 91691681. The reversal of 91691678 is 87619619.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60050 + ... + 61557.

It is an arithmetic number, because the mean of its divisors is an integer number (9576630).

Almost surely, 2^91691678 is an apocalyptic number.

91691678 is a deficient number, since it is larger than the sum of its proper divisors (61534402).

91691678 is a wasteful number, since it uses less digits than its factorization.

91691678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121651.

The product of its digits is 163296, while the sum is 47.

The square root of 91691678 is about 9575.5771627615. The cubic root of 91691678 is about 450.9308763405.

The spelling of 91691678 in words is "ninety-one million, six hundred ninety-one thousand, six hundred seventy-eight".