6778106780681 has 2 divisors, whose sum is σ = 6778106780682. Its totient is φ = 6778106780680.

The previous prime is 6778106780647. The next prime is 6778106780737. The reversal of 6778106780681 is 1860876018776.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5669561015056 + 1108545765625 = 2381084^2 + 1052875^2 .

It is a cyclic number.

It is not a de Polignac number, because 6778106780681 - 2³⁸ = 6503228873737 is a prime.

It is a super-2 number, since 2×6778106780681² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6778106780611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3389053390340 + 3389053390341.

It is an arithmetic number, because the mean of its divisors is an integer number (3389053390341).

Almost surely, 2^{6778106780681} is an apocalyptic number.

It is an amenable number.

6778106780681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6778106780681 is an equidigital number, since it uses as much as digits as its factorization.

6778106780681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 37933056, while the sum is 65.

The spelling of 6778106780681 in words is "six trillion, seven hundred seventy-eight billion, one hundred six million, seven hundred eighty thousand, six hundred eighty-one".