224231221 has 2 divisors, whose sum is σ = 224231222. Its totient is φ = 224231220.

The previous prime is 224231213. The next prime is 224231251. The reversal of 224231221 is 122132422.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 224100900 + 130321 = 14970^2 + 361^2 .

It is a cyclic number.

It is not a de Polignac number, because 224231221 - 2³ = 224231213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (224231251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112115610 + 112115611.

It is an arithmetic number, because the mean of its divisors is an integer number (112115611).

Almost surely, 2^224231221 is an apocalyptic number.

It is an amenable number.

224231221 is a deficient number, since it is larger than the sum of its proper divisors (1).

224231221 is an equidigital number, since it uses as much as digits as its factorization.

224231221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 384, while the sum is 19.

The square root of 224231221 is about 14974.3521061848. The cubic root of 224231221 is about 607.5266877357.

Adding to 224231221 its reverse (122132422), we get a palindrome (346363643).

The spelling of 224231221 in words is "two hundred twenty-four million, two hundred thirty-one thousand, two hundred twenty-one".