91987794 has 12 divisors (see below), whose sum is σ = 199306926. Its totient is φ = 30662592.

The previous prime is 91987783. The next prime is 91987801. The reversal of 91987794 is 49778919.

It can be written as a sum of positive squares in only one way, i.e., 51194025 + 40793769 = 7155^2 + 6387^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 91987794.

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 5 ways as a sum of consecutive naturals, for example, 2555199 + ... + 2555234.

Almost surely, 2^91987794 is an apocalyptic number.

91987794 is an abundant number, since it is smaller than the sum of its proper divisors (107319132).

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

91987794 is a wasteful number, since it uses less digits than its factorization.

91987794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5110441 (or 5110438 counting only the distinct ones).

The product of its digits is 1143072, while the sum is 54.

The square root of 91987794 is about 9591.0267437850. The cubic root of 91987794 is about 451.4157780822.

The spelling of 91987794 in words is "ninety-one million, nine hundred eighty-seven thousand, seven hundred ninety-four".