681855638673 has 64 divisors (see below), whose sum is σ = 1041223163904. Its totient is φ = 393139008000.

The previous prime is 681855638623. The next prime is 681855638713. The reversal of 681855638673 is 376836558186.

It is not a de Polignac number, because 681855638673 - 2¹⁴ = 681855622289 is a prime.

It is a super-2 number, since 2×681855638673² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (681855638603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 22911583 + ... + 22941323.

It is an arithmetic number, because the mean of its divisors is an integer number (16269111936).

Almost surely, 2^681855638673 is an apocalyptic number.

It is an amenable number.

681855638673 is a deficient number, since it is larger than the sum of its proper divisors (359367525231).

681855638673 is a wasteful number, since it uses less digits than its factorization.

681855638673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30166.

The product of its digits is 174182400, while the sum is 66.

The spelling of 681855638673 in words is "six hundred eighty-one billion, eight hundred fifty-five million, six hundred thirty-eight thousand, six hundred seventy-three".