723909 has 4 divisors (see below), whose sum is σ = 965216. Its totient is φ = 482604.

The previous prime is 723907. The next prime is 723913. The reversal of 723909 is 909327.

723909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 723909 - 2¹ = 723907 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (723901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120649 + ... + 120654.

It is an arithmetic number, because the mean of its divisors is an integer number (241304).

2⁷²³⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

723909 is a deficient number, since it is larger than the sum of its proper divisors (241307).

723909 is a wasteful number, since it uses less digits than its factorization.

723909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241306.

The product of its (nonzero) digits is 3402, while the sum is 30.

The square root of 723909 is about 850.8284198356. The cubic root of 723909 is about 89.7900042280.

The spelling of 723909 in words is "seven hundred twenty-three thousand, nine hundred nine".