721323 has 6 divisors (see below), whose sum is σ = 1041924. Its totient is φ = 480876.

The previous prime is 721321. The next prime is 721333. The reversal of 721323 is 323127.

It is not a de Polignac number, because 721323 - 2¹ = 721321 is a prime.

721323 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 721296 and 721305.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 721323.

It is not an unprimeable number, because it can be changed into a prime (721321) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40065 + ... + 40082.

It is an arithmetic number, because the mean of its divisors is an integer number (173654).

2⁷²¹³²³ is an apocalyptic number.

721323 is a deficient number, since it is larger than the sum of its proper divisors (320601).

721323 is a wasteful number, since it uses less digits than its factorization.

721323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80153 (or 80150 counting only the distinct ones).

The product of its digits is 252, while the sum is 18.

The square root of 721323 is about 849.3073648568. The cubic root of 721323 is about 89.6829585490.

The spelling of 721323 in words is "seven hundred twenty-one thousand, three hundred twenty-three", and thus it is an iban number.