681308756 has 12 divisors (see below), whose sum is σ = 1211836500. Its totient is φ = 335069760.

The previous prime is 681308743. The next prime is 681308759. The reversal of 681308756 is 657803186.

681308756 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 7075600 + 674233156 = 2660^2 + 25966^2 .

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681308759) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1395881 + ... + 1396368.

It is an arithmetic number, because the mean of its divisors is an integer number (100986375).

Almost surely, 2^681308756 is an apocalyptic number.

It is an amenable number.

681308756 is a deficient number, since it is larger than the sum of its proper divisors (530527744).

681308756 is a wasteful number, since it uses less digits than its factorization.

681308756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2792314 (or 2792312 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 44.

The square root of 681308756 is about 26101.8918088326. The cubic root of 681308756 is about 879.9297275153.

The spelling of 681308756 in words is "six hundred eighty-one million, three hundred eight thousand, seven hundred fifty-six".