91662391 has 4 divisors (see below), whose sum is σ = 92019312. Its totient is φ = 91305472.

The previous prime is 91662379. The next prime is 91662397. The reversal of 91662391 is 19326619.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91662391 - 2¹¹ = 91660343 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91662391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91662397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 178075 + ... + 178588.

It is an arithmetic number, because the mean of its divisors is an integer number (23004828).

Almost surely, 2^91662391 is an apocalyptic number.

91662391 is a deficient number, since it is larger than the sum of its proper divisors (356921).

91662391 is a wasteful number, since it uses less digits than its factorization.

91662391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356920.

The product of its digits is 17496, while the sum is 37.

The square root of 91662391 is about 9574.0477855503. The cubic root of 91662391 is about 450.8828610091.

The spelling of 91662391 in words is "ninety-one million, six hundred sixty-two thousand, three hundred ninety-one".