87998521 has 8 divisors (see below), whose sum is σ = 95251464. Its totient is φ = 80814720.

The previous prime is 87998513. The next prime is 87998531. The reversal of 87998521 is 12589978.

It can be written as a sum of positive squares in 4 ways, for example, as 36000000 + 51998521 = 6000^2 + 7211^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 87998521 - 2³ = 87998513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87998501) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 14620 + ... + 19741.

It is an arithmetic number, because the mean of its divisors is an integer number (11906433).

Almost surely, 2^87998521 is an apocalyptic number.

It is an amenable number.

87998521 is a deficient number, since it is larger than the sum of its proper divisors (7252943).

87998521 is a wasteful number, since it uses less digits than its factorization.

87998521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34571.

The product of its digits is 362880, while the sum is 49.

The square root of 87998521 is about 9380.7526883508. The cubic root of 87998521 is about 444.7935262313.

The spelling of 87998521 in words is "eighty-seven million, nine hundred ninety-eight thousand, five hundred twenty-one".