91689588 has 72 divisors (see below), whose sum is σ = 241297056. Its totient is φ = 29332800.

The previous prime is 91689583. The next prime is 91689623. The reversal of 91689588 is 88598619.

Its product of digits (1244160) is a multiple of the sum of its prime divisors (1080).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91689583) 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, 93943 + ... + 94913.

It is an arithmetic number, because the mean of its divisors is an integer number (3351348).

Almost surely, 2^91689588 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 91689588, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120648528).

91689588 is an abundant number, since it is smaller than the sum of its proper divisors (149607468).

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

91689588 is a wasteful number, since it uses less digits than its factorization.

91689588 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1085 (or 1080 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The square root of 91689588 is about 9575.4680303367. The cubic root of 91689588 is about 450.9274501746.

The spelling of 91689588 in words is "ninety-one million, six hundred eighty-nine thousand, five hundred eighty-eight".