723231221 has 8 divisors (see below), whose sum is σ = 776265624. Its totient is φ = 671362560.

The previous prime is 723231217. The next prime is 723231227. The reversal of 723231221 is 122132327.

It can be written as a sum of positive squares in 4 ways, for example, as 72420100 + 650811121 = 8510^2 + 25511^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 723231221 - 2² = 723231217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (723231227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 290150 + ... + 292631.

It is an arithmetic number, because the mean of its divisors is an integer number (97033203).

Almost surely, 2^723231221 is an apocalyptic number.

It is an amenable number.

723231221 is a deficient number, since it is larger than the sum of its proper divisors (53034403).

723231221 is a wasteful number, since it uses less digits than its factorization.

723231221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582871.

The product of its digits is 1008, while the sum is 23.

The square root of 723231221 is about 26892.9585765494. The cubic root of 723231221 is about 897.6197272015.

Adding to 723231221 its reverse (122132327), we get a palindrome (845363548).

The spelling of 723231221 in words is "seven hundred twenty-three million, two hundred thirty-one thousand, two hundred twenty-one".