91990764 has 54 divisors (see below), whose sum is σ = 240365580. Its totient is φ = 29663280.

The previous prime is 91990753. The next prime is 91990771. The reversal of 91990764 is 46709919.

It is a super-2 number, since 2×91990764² = 16924601322607392, which contains 22 as substring.

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 33267 + ... + 35925.

Almost surely, 2^91990764 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 91990764, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120182790).

91990764 is an abundant number, since it is smaller than the sum of its proper divisors (148374816).

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

91990764 is a wasteful number, since it uses less digits than its factorization.

91990764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2731 (or 2695 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 91990764 is about 9591.1815747592. The cubic root of 91990764 is about 451.4206363008.

The spelling of 91990764 in words is "ninety-one million, nine hundred ninety thousand, seven hundred sixty-four".