6817116661 has 2 divisors, whose sum is σ = 6817116662. Its totient is φ = 6817116660.

The previous prime is 6817116653. The next prime is 6817116667. The reversal of 6817116661 is 1666117186.

6817116661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5993082225 + 824034436 = 77415^2 + 28706^2 .

It is a cyclic number.

It is not a de Polignac number, because 6817116661 - 2³ = 6817116653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6817116667) 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, 3408558330 + 3408558331.

It is an arithmetic number, because the mean of its divisors is an integer number (3408558331).

Almost surely, 2^6817116661 is an apocalyptic number.

It is an amenable number.

6817116661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6817116661 is an equidigital number, since it uses as much as digits as its factorization.

6817116661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The square root of 6817116661 is about 82565.8322855163. The cubic root of 6817116661 is about 1896.1247571010.

The spelling of 6817116661 in words is "six billion, eight hundred seventeen million, one hundred sixteen thousand, six hundred sixty-one".