681838782329951 has 4 divisors (see below), whose sum is σ = 681839095032504. Its totient is φ = 681838469627400.

The previous prime is 681838782329917. The next prime is 681838782329953. The reversal of 681838782329951 is 159923287838186.

It is a happy number.

681838782329951 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681838782329951 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681838782329953) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 153057440 + ... + 157449221.

It is an arithmetic number, because the mean of its divisors is an integer number (170459773758126).

Almost surely, 2^{681838782329951} is an apocalyptic number.

681838782329951 is a deficient number, since it is larger than the sum of its proper divisors (312702553).

681838782329951 is a wasteful number, since it uses less digits than its factorization.

681838782329951 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312702552.

The product of its digits is 2508226560, while the sum is 80.

The spelling of 681838782329951 in words is "six hundred eighty-one trillion, eight hundred thirty-eight billion, seven hundred eighty-two million, three hundred twenty-nine thousand, nine hundred fifty-one".