91644372 has 60 divisors (see below), whose sum is σ = 252202720. Its totient is φ = 28938384.

The previous prime is 91644361. The next prime is 91644373. The reversal of 91644372 is 27344619.

91644372 is a `hidden beast` number, since 9 + 1 + 644 + 3 + 7 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91644373) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1288 + ... + 13599.

Almost surely, 2^91644372 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 91644372, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126101360).

91644372 is an abundant number, since it is smaller than the sum of its proper divisors (160558348).

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

91644372 is a wasteful number, since it uses less digits than its factorization.

91644372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14922 (or 14911 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 91644372 is about 9573.1067057669. The cubic root of 91644372 is about 450.8533142102.

The spelling of 91644372 in words is "ninety-one million, six hundred forty-four thousand, three hundred seventy-two".