87117517 has 2 divisors, whose sum is σ = 87117518. Its totient is φ = 87117516.

The previous prime is 87117509. The next prime is 87117529. The reversal of 87117517 is 71571178.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58537801 + 28579716 = 7651^2 + 5346^2 .

It is a cyclic number.

It is not a de Polignac number, because 87117517 - 2³ = 87117509 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 (87111517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43558758 + 43558759.

It is an arithmetic number, because the mean of its divisors is an integer number (43558759).

Almost surely, 2^87117517 is an apocalyptic number.

It is an amenable number.

87117517 is a deficient number, since it is larger than the sum of its proper divisors (1).

87117517 is an equidigital number, since it uses as much as digits as its factorization.

87117517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13720, while the sum is 37.

The square root of 87117517 is about 9333.6764996436. The cubic root of 87117517 is about 443.3041832958.

The spelling of 87117517 in words is "eighty-seven million, one hundred seventeen thousand, five hundred seventeen".