91987924 has 12 divisors (see below), whose sum is σ = 183975904. Its totient is φ = 39423384.

The previous prime is 91987919. The next prime is 91987927. The reversal of 91987924 is 42978919.

91987924 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91987927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1642614 + ... + 1642669.

Almost surely, 2^91987924 is an apocalyptic number.

It is an amenable number.

91987924 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

91987924 is a wasteful number, since it uses less digits than its factorization.

91987924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3285294 (or 3285292 counting only the distinct ones).

The product of its digits is 326592, while the sum is 49.

The square root of 91987924 is about 9591.0335209507. The cubic root of 91987924 is about 451.4159907337.

The spelling of 91987924 in words is "ninety-one million, nine hundred eighty-seven thousand, nine hundred twenty-four".