680721413 has 2 divisors, whose sum is σ = 680721414. Its totient is φ = 680721412.

The previous prime is 680721403. The next prime is 680721421. The reversal of 680721413 is 314127086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 448677124 + 232044289 = 21182^2 + 15233^2 .

It is a cyclic number.

It is not a de Polignac number, because 680721413 - 2¹⁴ = 680705029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 680721413.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (680721403) 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, 340360706 + 340360707.

It is an arithmetic number, because the mean of its divisors is an integer number (340360707).

Almost surely, 2^680721413 is an apocalyptic number.

It is an amenable number.

680721413 is a deficient number, since it is larger than the sum of its proper divisors (1).

680721413 is an equidigital number, since it uses as much as digits as its factorization.

680721413 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 680721413 is about 26090.6384168728. The cubic root of 680721413 is about 879.6767980633.

Adding to 680721413 its reverse (314127086), we get a palindrome (994848499).

The spelling of 680721413 in words is "six hundred eighty million, seven hundred twenty-one thousand, four hundred thirteen".