8398566809 has 2 divisors, whose sum is σ = 8398566810. Its totient is φ = 8398566808.

The previous prime is 8398566643. The next prime is 8398566829. The reversal of 8398566809 is 9086658938.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6127758400 + 2270808409 = 78280^2 + 47653^2 .

It is a cyclic number.

It is not a de Polignac number, because 8398566809 - 2²⁴ = 8381789593 is a prime.

It is not a weakly prime, because it can be changed into another prime (8398566829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4199283404 + 4199283405.

It is an arithmetic number, because the mean of its divisors is an integer number (4199283405).

Almost surely, 2^8398566809 is an apocalyptic number.

It is an amenable number.

8398566809 is a deficient number, since it is larger than the sum of its proper divisors (1).

8398566809 is an equidigital number, since it uses as much as digits as its factorization.

8398566809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22394880, while the sum is 62.

The square root of 8398566809 is about 91643.6948676776. The cubic root of 8398566809 is about 2032.6770967277.

The spelling of 8398566809 in words is "eight billion, three hundred ninety-eight million, five hundred sixty-six thousand, eight hundred nine".