721793 has 2 divisors, whose sum is σ = 721794. Its totient is φ = 721792.

The previous prime is 721783. The next prime is 721843. The reversal of 721793 is 397127.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 552049 + 169744 = 743^2 + 412^2 .

It is an emirp because it is prime and its reverse (397127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 721793 - 2¹² = 717697 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 721793.

It is not a weakly prime, because it can be changed into another prime (721703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360896 + 360897.

It is an arithmetic number, because the mean of its divisors is an integer number (360897).

2⁷²¹⁷⁹³ is an apocalyptic number.

It is an amenable number.

721793 is a deficient number, since it is larger than the sum of its proper divisors (1).

721793 is an equidigital number, since it uses as much as digits as its factorization.

721793 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2646, while the sum is 29.

The square root of 721793 is about 849.5840158572. The cubic root of 721793 is about 89.7024328756.

The spelling of 721793 in words is "seven hundred twenty-one thousand, seven hundred ninety-three".