91977372 has 72 divisors (see below), whose sum is σ = 243501440. Its totient is φ = 29237760.

The previous prime is 91977359. The next prime is 91977373. The reversal of 91977372 is 27377919.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91977373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80904 + ... + 82032.

Almost surely, 2^91977372 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 91977372, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121750720).

91977372 is an abundant number, since it is smaller than the sum of its proper divisors (151524068).

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

91977372 is a wasteful number, since it uses less digits than its factorization.

91977372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1243 (or 1238 counting only the distinct ones).

The product of its digits is 166698, while the sum is 45.

The square root of 91977372 is about 9590.4834080457. The cubic root of 91977372 is about 451.3987293242.

The spelling of 91977372 in words is "ninety-one million, nine hundred seventy-seven thousand, three hundred seventy-two".