221323243 has 4 divisors (see below), whose sum is σ = 221823288. Its totient is φ = 220823200.

The previous prime is 221323237. The next prime is 221323253. The reversal of 221323243 is 342323122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221323243 - 2⁵ = 221323211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221323213) 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 3 ways as a sum of consecutive naturals, for example, 249358 + ... + 250243.

It is an arithmetic number, because the mean of its divisors is an integer number (55455822).

Almost surely, 2^221323243 is an apocalyptic number.

221323243 is a deficient number, since it is larger than the sum of its proper divisors (500045).

221323243 is an equidigital number, since it uses as much as digits as its factorization.

221323243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500044.

The product of its digits is 1728, while the sum is 22.

The square root of 221323243 is about 14876.9366134295. The cubic root of 221323243 is about 604.8889835686. Note that the first 3 decimals are identical.

Adding to 221323243 its reverse (342323122), we get a palindrome (563646365).

The spelling of 221323243 in words is "two hundred twenty-one million, three hundred twenty-three thousand, two hundred forty-three".