681307543861 has 12 divisors (see below), whose sum is σ = 799948363968. Its totient is φ = 578520152952.

The previous prime is 681307543841. The next prime is 681307543897. The reversal of 681307543861 is 168345703186.

It is a happy number.

It is not a de Polignac number, because 681307543861 - 2⁹ = 681307543349 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 681307543799 and 681307543808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681307543841) 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 11 ways as a sum of consecutive naturals, for example, 64967821 + ... + 64978306.

It is an arithmetic number, because the mean of its divisors is an integer number (66662363664).

Almost surely, 2^681307543861 is an apocalyptic number.

It is an amenable number.

681307543861 is a deficient number, since it is larger than the sum of its proper divisors (118640820107).

681307543861 is a wasteful number, since it uses less digits than its factorization.

681307543861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129946248 (or 129946241 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 52.

The spelling of 681307543861 in words is "six hundred eighty-one billion, three hundred seven million, five hundred forty-three thousand, eight hundred sixty-one".