681909070909185 has 64 divisors (see below), whose sum is σ = 1385469537830400. Its totient is φ = 311729075963136.

The previous prime is 681909070909181. The next prime is 681909070909207. The reversal of 681909070909185 is 581909070909186.

It is not a de Polignac number, because 681909070909185 - 2² = 681909070909181 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (681909070909181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 553333107 + ... + 554564103.

It is an arithmetic number, because the mean of its divisors is an integer number (21647961528600).

Almost surely, 2^{681909070909185} is an apocalyptic number.

It is an amenable number.

681909070909185 is an abundant number, since it is smaller than the sum of its proper divisors (703560466921215).

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

681909070909185 is a wasteful number, since it uses less digits than its factorization.

681909070909185 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1817207 (or 1817201 counting only the distinct ones).

The product of its (nonzero) digits is 88179840, while the sum is 72.

Subtracting from 681909070909185 its reverse (581909070909186), we obtain a palindrome (99999999999999).

The spelling of 681909070909185 in words is "six hundred eighty-one trillion, nine hundred nine billion, seventy million, nine hundred nine thousand, one hundred eighty-five".