681309140 has 12 divisors (see below), whose sum is σ = 1430749236. Its totient is φ = 272523648.

The previous prime is 681309137. The next prime is 681309143. The reversal of 681309140 is 41903186.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (681309137) and next prime (681309143).

It can be written as a sum of positive squares in 2 ways, for example, as 537405124 + 143904016 = 23182^2 + 11996^2 .

It is a junction number, because it is equal to n+sod(n) for n = 681309097 and 681309106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681309143) 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 in 3 ways as a sum of consecutive naturals, for example, 17032709 + ... + 17032748.

It is an arithmetic number, because the mean of its divisors is an integer number (119229103).

Almost surely, 2^681309140 is an apocalyptic number.

It is an amenable number.

681309140 is an abundant number, since it is smaller than the sum of its proper divisors (749440096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

681309140 is a wasteful number, since it uses less digits than its factorization.

681309140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34065466 (or 34065464 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 681309140 is about 26101.8991646202. The cubic root of 681309140 is about 879.9298928309.

The spelling of 681309140 in words is "six hundred eighty-one million, three hundred nine thousand, one hundred forty".