91977856 has 32 divisors (see below), whose sum is σ = 188199180. Its totient is φ = 44743680.

The previous prime is 91977811. The next prime is 91977863. The reversal of 91977856 is 65877919.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 66977856 + 25000000 = 8184^2 + 5000^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4975 + ... + 14446.

Almost surely, 2^91977856 is an apocalyptic number.

It is an amenable number.

91977856 is an abundant number, since it is smaller than the sum of its proper divisors (96221324).

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

91977856 is a wasteful number, since it uses less digits than its factorization.

91977856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19472 (or 19460 counting only the distinct ones).

The product of its digits is 952560, while the sum is 52.

The square root of 91977856 is about 9590.5086413600. The cubic root of 91977856 is about 451.3995211008.

The spelling of 91977856 in words is "ninety-one million, nine hundred seventy-seven thousand, eight hundred fifty-six".