87521317 has 8 divisors (see below), whose sum is σ = 96801656. Its totient is φ = 78604992.

The previous prime is 87521303. The next prime is 87521341. The reversal of 87521317 is 71312578.

It can be written as a sum of positive squares in 4 ways, for example, as 7257636 + 80263681 = 2694^2 + 8959^2 .

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 87521317 - 2¹¹ = 87519269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87521017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90498 + ... + 91459.

It is an arithmetic number, because the mean of its divisors is an integer number (12100207).

Almost surely, 2^87521317 is an apocalyptic number.

It is an amenable number.

87521317 is a deficient number, since it is larger than the sum of its proper divisors (9280339).

87521317 is a wasteful number, since it uses less digits than its factorization.

87521317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182007.

The product of its digits is 11760, while the sum is 34.

The square root of 87521317 is about 9355.2828391236. The cubic root of 87521317 is about 443.9880502289.

The spelling of 87521317 in words is "eighty-seven million, five hundred twenty-one thousand, three hundred seventeen".