6800816681 has 2 divisors, whose sum is σ = 6800816682. Its totient is φ = 6800816680.

The previous prime is 6800816653. The next prime is 6800816683. The reversal of 6800816681 is 1866180086.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5821690000 + 979126681 = 76300^2 + 31291^2 .

It is a cyclic number.

It is not a de Polignac number, because 6800816681 - 2²² = 6796622377 is a prime.

It is a super-2 number, since 2×6800816681² = 92502215057135711522, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 6800816683, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (6800816683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3400408340 + 3400408341.

It is an arithmetic number, because the mean of its divisors is an integer number (3400408341).

Almost surely, 2^6800816681 is an apocalyptic number.

6800816681 is the 44081-st centered heptagonal number.

It is an amenable number.

6800816681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6800816681 is an equidigital number, since it uses as much as digits as its factorization.

6800816681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 110592, while the sum is 44.

The square root of 6800816681 is about 82467.0642196022. The cubic root of 6800816681 is about 1894.6123160388.

The spelling of 6800816681 in words is "six billion, eight hundred million, eight hundred sixteen thousand, six hundred eighty-one".