87806681 has 2 divisors, whose sum is σ = 87806682. Its totient is φ = 87806680.

The previous prime is 87806671. The next prime is 87806689. The reversal of 87806681 is 18660878.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56625625 + 31181056 = 7525^2 + 5584^2 .

It is a cyclic number.

It is not a de Polignac number, because 87806681 - 2²² = 83612377 is a prime.

It is a super-2 number, since 2×87806681² = 15420026456471522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (87806689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43903340 + 43903341.

It is an arithmetic number, because the mean of its divisors is an integer number (43903341).

Almost surely, 2^87806681 is an apocalyptic number.

It is an amenable number.

87806681 is a deficient number, since it is larger than the sum of its proper divisors (1).

87806681 is an equidigital number, since it uses as much as digits as its factorization.

87806681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 129024, while the sum is 44.

The square root of 87806681 is about 9370.5219171613. The cubic root of 87806681 is about 444.4700690064.

The spelling of 87806681 in words is "eighty-seven million, eight hundred six thousand, six hundred eighty-one".