681316717 has 2 divisors, whose sum is σ = 681316718. Its totient is φ = 681316716.

The previous prime is 681316693. The next prime is 681316733. The reversal of 681316717 is 717613186.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 394657956 + 286658761 = 19866^2 + 16931^2 .

It is a cyclic number.

It is not a de Polignac number, because 681316717 - 2¹⁵ = 681283949 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 681316717.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681316217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340658358 + 340658359.

It is an arithmetic number, because the mean of its divisors is an integer number (340658359).

Almost surely, 2^681316717 is an apocalyptic number.

It is an amenable number.

681316717 is a deficient number, since it is larger than the sum of its proper divisors (1).

681316717 is an equidigital number, since it uses as much as digits as its factorization.

681316717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42336, while the sum is 40.

The square root of 681316717 is about 26102.0443069121. The cubic root of 681316717 is about 879.9331547882.

The spelling of 681316717 in words is "six hundred eighty-one million, three hundred sixteen thousand, seven hundred seventeen".