91889964 has 144 divisors (see below), whose sum is σ = 261975168. Its totient is φ = 28055808.

The previous prime is 91889929. The next prime is 91889971. The reversal of 91889964 is 46998819.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 91889964.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1107067 + ... + 1107149.

It is an arithmetic number, because the mean of its divisors is an integer number (1819272).

Almost surely, 2^91889964 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 91889964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130987584).

91889964 is an abundant number, since it is smaller than the sum of its proper divisors (170085204).

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

91889964 is a wasteful number, since it uses less digits than its factorization.

91889964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186 (or 172 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 54.

The square root of 91889964 is about 9585.9253074495. The cubic root of 91889964 is about 451.2556928198.

The spelling of 91889964 in words is "ninety-one million, eight hundred eighty-nine thousand, nine hundred sixty-four".