87186661 has 2 divisors, whose sum is σ = 87186662. Its totient is φ = 87186660.

The previous prime is 87186613. The next prime is 87186667. The reversal of 87186661 is 16668178.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77545636 + 9641025 = 8806^2 + 3105^2 .

It is a cyclic number.

It is not a de Polignac number, because 87186661 - 2¹¹ = 87184613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87186667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43593330 + 43593331.

It is an arithmetic number, because the mean of its divisors is an integer number (43593331).

Almost surely, 2^87186661 is an apocalyptic number.

It is an amenable number.

87186661 is a deficient number, since it is larger than the sum of its proper divisors (1).

87186661 is an equidigital number, since it uses as much as digits as its factorization.

87186661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 43.

The square root of 87186661 is about 9337.3797716490. The cubic root of 87186661 is about 443.4214338012.

The spelling of 87186661 in words is "eighty-seven million, one hundred eighty-six thousand, six hundred sixty-one".