6698966556809 has 2 divisors, whose sum is σ = 6698966556810. Its totient is φ = 6698966556808.

The previous prime is 6698966556797. The next prime is 6698966556829. The reversal of 6698966556809 is 9086556698966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6062207244025 + 636759312784 = 2462155^2 + 797972^2 .

It is a cyclic number.

It is not a de Polignac number, because 6698966556809 - 2²⁰ = 6698965508233 is a prime.

It is not a weakly prime, because it can be changed into another prime (6698966556829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3349483278404 + 3349483278405.

It is an arithmetic number, because the mean of its divisors is an integer number (3349483278405).

Almost surely, 2^{6698966556809} is an apocalyptic number.

It is an amenable number.

6698966556809 is a deficient number, since it is larger than the sum of its proper divisors (1).

6698966556809 is an equidigital number, since it uses as much as digits as its factorization.

6698966556809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9069926400, while the sum is 83.

The spelling of 6698966556809 in words is "six trillion, six hundred ninety-eight billion, nine hundred sixty-six million, five hundred fifty-six thousand, eight hundred nine".