681838782329953 has 2 divisors, whose sum is σ = 681838782329954. Its totient is φ = 681838782329952.

The previous prime is 681838782329917. The next prime is 681838782329981. The reversal of 681838782329953 is 359923287838186.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 657334579500369 + 24504202829584 = 25638537^2 + 4950172^2 .

It is a cyclic number.

It is not a de Polignac number, because 681838782329953 - 2²⁵ = 681838748775521 is a prime.

It is not a weakly prime, because it can be changed into another prime (681838782329993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340919391164976 + 340919391164977.

It is an arithmetic number, because the mean of its divisors is an integer number (340919391164977).

Almost surely, 2^{681838782329953} is an apocalyptic number.

It is an amenable number.

681838782329953 is a deficient number, since it is larger than the sum of its proper divisors (1).

681838782329953 is an equidigital number, since it uses as much as digits as its factorization.

681838782329953 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7524679680, while the sum is 82.

The spelling of 681838782329953 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-three".