6778861 has 2 divisors, whose sum is σ = 6778862. Its totient is φ = 6778860.

The previous prime is 6778841. The next prime is 6778921. The reversal of 6778861 is 1688776.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5788836 + 990025 = 2406^2 + 995^2 .

It is a cyclic number.

It is not a de Polignac number, because 6778861 - 2⁵ = 6778829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6778831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3389430 + 3389431.

It is an arithmetic number, because the mean of its divisors is an integer number (3389431).

Almost surely, 2^6778861 is an apocalyptic number.

It is an amenable number.

6778861 is a deficient number, since it is larger than the sum of its proper divisors (1).

6778861 is an equidigital number, since it uses as much as digits as its factorization.

6778861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 112896, while the sum is 43.

The square root of 6778861 is about 2603.6245889145. The cubic root of 6778861 is about 189.2571269581.

The spelling of 6778861 in words is "six million, seven hundred seventy-eight thousand, eight hundred sixty-one".