221322213 has 72 divisors (see below), whose sum is σ = 390490880. Its totient is φ = 122821920.

The previous prime is 221322193. The next prime is 221322293. The reversal of 221322213 is 312223122.

It is not a de Polignac number, because 221322213 - 2⁸ = 221321957 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 (221322293) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2801508 + ... + 2801586.

Almost surely, 2^221322213 is an apocalyptic number.

It is an amenable number.

221322213 is a deficient number, since it is larger than the sum of its proper divisors (169168667).

221322213 is an frugal number, since it uses more digits than its factorization.

221322213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171 (or 150 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 221322213 is about 14876.9019960474. The cubic root of 221322213 is about 604.8880452177. Note that the first 3 decimals are identical.

Adding to 221322213 its reverse (312223122), we get a palindrome (533545335).

Subtracting 221322213 from its reverse (312223122), we obtain a palindrome (90900909).

The spelling of 221322213 in words is "two hundred twenty-one million, three hundred twenty-two thousand, two hundred thirteen".