724721 has 2 divisors, whose sum is σ = 724722. Its totient is φ = 724720.

The previous prime is 724651. The next prime is 724723. The reversal of 724721 is 127427.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 474721 + 250000 = 689^2 + 500^2 .

It is a cyclic number.

It is not a de Polignac number, because 724721 - 2¹⁸ = 462577 is a prime.

It is a Sophie Germain prime.

Together with 724723, it forms a pair of twin primes.

It is a Chen 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 724721.

It is not a weakly prime, because it can be changed into another prime (724723) 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, 362360 + 362361.

It is an arithmetic number, because the mean of its divisors is an integer number (362361).

2⁷²⁴⁷²¹ is an apocalyptic number.

It is an amenable number.

724721 is a deficient number, since it is larger than the sum of its proper divisors (1).

724721 is an equidigital number, since it uses as much as digits as its factorization.

724721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 784, while the sum is 23.

The square root of 724721 is about 851.3054680900. The cubic root of 724721 is about 89.8235638051.

The spelling of 724721 in words is "seven hundred twenty-four thousand, seven hundred twenty-one", and thus it is an iban number.