91864656 has 120 divisors (see below), whose sum is σ = 285981696. Its totient is φ = 27336960.

The previous prime is 91864637. The next prime is 91864657. The reversal of 91864656 is 65646819.

91864656 is a `hidden beast` number, since 9 + 186 + 465 + 6 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91864657) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57241 + ... + 58823.

Almost surely, 2^91864656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91864656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142990848).

91864656 is an abundant number, since it is smaller than the sum of its proper divisors (194117040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91864656 is a wasteful number, since it uses less digits than its factorization.

91864656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1641 (or 1632 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 91864656 is about 9584.6051561867. The cubic root of 91864656 is about 451.2142612815.

The spelling of 91864656 in words is "ninety-one million, eight hundred sixty-four thousand, six hundred fifty-six".