221205223 has 2 divisors, whose sum is σ = 221205224. Its totient is φ = 221205222.

The previous prime is 221205161. The next prime is 221205227. The reversal of 221205223 is 322502122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221205223 - 2¹⁷ = 221074151 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221205223.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221205227) 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 as a sum of consecutive naturals, namely, 110602611 + 110602612.

It is an arithmetic number, because the mean of its divisors is an integer number (110602612).

Almost surely, 2^221205223 is an apocalyptic number.

221205223 is a deficient number, since it is larger than the sum of its proper divisors (1).

221205223 is an equidigital number, since it uses as much as digits as its factorization.

221205223 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 221205223 is about 14872.9695420921. The cubic root of 221205223 is about 604.7814459991.

Adding to 221205223 its reverse (322502122), we get a palindrome (543707345).

The spelling of 221205223 in words is "two hundred twenty-one million, two hundred five thousand, two hundred twenty-three".