681806777 has 12 divisors (see below), whose sum is σ = 747645696. Its totient is φ = 620992320.

The previous prime is 681806771. The next prime is 681806803. The reversal of 681806777 is 777608186.

681806777 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-681806777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681806771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29093 + ... + 47010.

It is an arithmetic number, because the mean of its divisors is an integer number (62303808).

Almost surely, 2^681806777 is an apocalyptic number.

It is an amenable number.

681806777 is a deficient number, since it is larger than the sum of its proper divisors (65838919).

681806777 is a wasteful number, since it uses less digits than its factorization.

681806777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76168 (or 76151 counting only the distinct ones).

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

The square root of 681806777 is about 26111.4300067997. The cubic root of 681806777 is about 880.1440780796.

The spelling of 681806777 in words is "six hundred eighty-one million, eight hundred six thousand, seven hundred seventy-seven".