87557990 has 32 divisors (see below), whose sum is σ = 179716320. Its totient is φ = 30426624.

The previous prime is 87557971. The next prime is 87557999. The reversal of 87557990 is 9975578.

It is a super-2 number, since 2×87557990² = 15332803225680200, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87557999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17600 + ... + 22019.

It is an arithmetic number, because the mean of its divisors is an integer number (5616135).

Almost surely, 2^87557990 is an apocalyptic number.

87557990 is an abundant number, since it is smaller than the sum of its proper divisors (92158330).

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

87557990 is a wasteful number, since it uses less digits than its factorization.

87557990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39656.

The product of its (nonzero) digits is 793800, while the sum is 50.

The square root of 87557990 is about 9357.2426494133. The cubic root of 87557990 is about 444.0500545522.

The spelling of 87557990 in words is "eighty-seven million, five hundred fifty-seven thousand, nine hundred ninety".