681302813 has 2 divisors, whose sum is σ = 681302814. Its totient is φ = 681302812.

The previous prime is 681302767. The next prime is 681302821. The reversal of 681302813 is 318203186.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 613701529 + 67601284 = 24773^2 + 8222^2 .

It is a cyclic number.

It is not a de Polignac number, because 681302813 - 2⁶ = 681302749 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 681302813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681302213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340651406 + 340651407.

It is an arithmetic number, because the mean of its divisors is an integer number (340651407).

Almost surely, 2^681302813 is an apocalyptic number.

It is an amenable number.

681302813 is a deficient number, since it is larger than the sum of its proper divisors (1).

681302813 is an equidigital number, since it uses as much as digits as its factorization.

681302813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 681302813 is about 26101.7779662612. Note that the first 3 decimals coincide. The cubic root of 681302813 is about 879.9271689897.

Adding to 681302813 its reverse (318203186), we get a palindrome (999505999).

The spelling of 681302813 in words is "six hundred eighty-one million, three hundred two thousand, eight hundred thirteen".