681391268 has 12 divisors (see below), whose sum is σ = 1192969932. Its totient is φ = 340542720.

The previous prime is 681391231. The next prime is 681391303. The reversal of 681391268 is 862193186.

It can be written as a sum of positive squares in 2 ways, for example, as 392119204 + 289272064 = 19802^2 + 17008^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27893 + ... + 46268.

It is an arithmetic number, because the mean of its divisors is an integer number (99414161).

Almost surely, 2^681391268 is an apocalyptic number.

It is an amenable number.

681391268 is a deficient number, since it is larger than the sum of its proper divisors (511578664).

681391268 is a wasteful number, since it uses less digits than its factorization.

681391268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76462 (or 76460 counting only the distinct ones).

The product of its digits is 124416, while the sum is 44.

The square root of 681391268 is about 26103.4723360705. The cubic root of 681391268 is about 879.9652482833.

The spelling of 681391268 in words is "six hundred eighty-one million, three hundred ninety-one thousand, two hundred sixty-eight".