87531517 has 2 divisors, whose sum is σ = 87531518. Its totient is φ = 87531516.

The previous prime is 87531511. The next prime is 87531553. The reversal of 87531517 is 71513578.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46430596 + 41100921 = 6814^2 + 6411^2 .

It is a cyclic number.

It is not a de Polignac number, because 87531517 - 2¹¹ = 87529469 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87531511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43765758 + 43765759.

It is an arithmetic number, because the mean of its divisors is an integer number (43765759).

Almost surely, 2^87531517 is an apocalyptic number.

It is an amenable number.

87531517 is a deficient number, since it is larger than the sum of its proper divisors (1).

87531517 is an equidigital number, since it uses as much as digits as its factorization.

87531517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 29400, while the sum is 37.

The square root of 87531517 is about 9355.8279697737. The cubic root of 87531517 is about 444.0052974641.

The spelling of 87531517 in words is "eighty-seven million, five hundred thirty-one thousand, five hundred seventeen".