721907713 has 2 divisors, whose sum is σ = 721907714. Its totient is φ = 721907712.

The previous prime is 721907699. The next prime is 721907741. The reversal of 721907713 is 317709127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 457617664 + 264290049 = 21392^2 + 16257^2 .

It is a cyclic number.

It is not a de Polignac number, because 721907713 - 2⁹ = 721907201 is a prime.

It is not a weakly prime, because it can be changed into another prime (721907773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360953856 + 360953857.

It is an arithmetic number, because the mean of its divisors is an integer number (360953857).

Almost surely, 2^721907713 is an apocalyptic number.

It is an amenable number.

721907713 is a deficient number, since it is larger than the sum of its proper divisors (1).

721907713 is an equidigital number, since it uses as much as digits as its factorization.

721907713 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18522, while the sum is 37.

The square root of 721907713 is about 26868.3403469585. The cubic root of 721907713 is about 897.0718469504.

The spelling of 721907713 in words is "seven hundred twenty-one million, nine hundred seven thousand, seven hundred thirteen".