87989724 has 18 divisors (see below), whose sum is σ = 222418560. Its totient is φ = 29329896.

The previous prime is 87989723. The next prime is 87989809. The reversal of 87989724 is 42798978.

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87989723) 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 5 ways as a sum of consecutive naturals, for example, 1222044 + ... + 1222115.

Almost surely, 2^87989724 is an apocalyptic number.

It is an amenable number.

87989724 is an abundant number, since it is smaller than the sum of its proper divisors (134428836).

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

87989724 is a wasteful number, since it uses less digits than its factorization.

87989724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2444169 (or 2444164 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

The square root of 87989724 is about 9380.2837910161. The cubic root of 87989724 is about 444.7787040919.

The spelling of 87989724 in words is "eighty-seven million, nine hundred eighty-nine thousand, seven hundred twenty-four".