8643688609 has 2 divisors, whose sum is σ = 8643688610. Its totient is φ = 8643688608.

The previous prime is 8643688591. The next prime is 8643688657. The reversal of 8643688609 is 9068863468.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8233747600 + 409941009 = 90740^2 + 20247^2 .

It is a cyclic number.

It is not a de Polignac number, because 8643688609 - 2¹³ = 8643680417 is a prime.

It is not a weakly prime, because it can be changed into another prime (8643686609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4321844304 + 4321844305.

It is an arithmetic number, because the mean of its divisors is an integer number (4321844305).

Almost surely, 2^8643688609 is an apocalyptic number.

It is an amenable number.

8643688609 is a deficient number, since it is larger than the sum of its proper divisors (1).

8643688609 is an equidigital number, since it uses as much as digits as its factorization.

8643688609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11943936, while the sum is 58.

The square root of 8643688609 is about 92971.4397489896. The cubic root of 8643688609 is about 2052.2631052382.

The spelling of 8643688609 in words is "eight billion, six hundred forty-three million, six hundred eighty-eight thousand, six hundred nine".