681907063889 has 2 divisors, whose sum is σ = 681907063890. Its totient is φ = 681907063888.

The previous prime is 681907063883. The next prime is 681907063913. The reversal of 681907063889 is 988360709186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 620101126225 + 61805937664 = 787465^2 + 248608^2 .

It is a cyclic number.

It is not a de Polignac number, because 681907063889 - 2²⁰ = 681906015313 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (681907063883) 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 as a sum of consecutive naturals, namely, 340953531944 + 340953531945.

It is an arithmetic number, because the mean of its divisors is an integer number (340953531945).

Almost surely, 2^681907063889 is an apocalyptic number.

It is an amenable number.

681907063889 is a deficient number, since it is larger than the sum of its proper divisors (1).

681907063889 is an equidigital number, since it uses as much as digits as its factorization.

681907063889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31352832, while the sum is 65.

The spelling of 681907063889 in words is "six hundred eighty-one billion, nine hundred seven million, sixty-three thousand, eight hundred eighty-nine".