776870681 has 2 divisors, whose sum is σ = 776870682. Its totient is φ = 776870680.

The previous prime is 776870669. The next prime is 776870683. The reversal of 776870681 is 186078677.

776870681 is digitally balanced in base 2, 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., 756250000 + 20620681 = 27500^2 + 4541^2 .

It is a cyclic number.

It is not a de Polignac number, because 776870681 - 2⁶ = 776870617 is a prime.

It is a super-2 number, since 2×776870681² = 1207056109994807522, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 776870683, 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 (776870683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 388435340 + 388435341.

It is an arithmetic number, because the mean of its divisors is an integer number (388435341).

Almost surely, 2^776870681 is an apocalyptic number.

It is an amenable number.

776870681 is a deficient number, since it is larger than the sum of its proper divisors (1).

776870681 is an equidigital number, since it uses as much as digits as its factorization.

776870681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 790272, while the sum is 50.

The square root of 776870681 is about 27872.3999863664. The cubic root of 776870681 is about 919.2837371605.

The spelling of 776870681 in words is "seven hundred seventy-six million, eight hundred seventy thousand, six hundred eighty-one".