12242221 has 2 divisors, whose sum is σ = 12242222. Its totient is φ = 12242220.

The previous prime is 12242203. The next prime is 12242257. The reversal of 12242221 is 12224221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11485321 + 756900 = 3389^2 + 870^2 .

It is an emirp because it is prime and its reverse (12224221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12242221 - 2⁵ = 12242189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12242195 and 12242204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12242201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6121110 + 6121111.

It is an arithmetic number, because the mean of its divisors is an integer number (6121111).

Almost surely, 2^12242221 is an apocalyptic number.

It is an amenable number.

12242221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12242221 is an equidigital number, since it uses as much as digits as its factorization.

12242221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 128, while the sum is 16.

The square root of 12242221 is about 3498.8885378074. Note that the first 3 decimals coincide. The cubic root of 12242221 is about 230.4730089183.

Adding to 12242221 its reverse (12224221), we get a palindrome (24466442).

The spelling of 12242221 in words is "twelve million, two hundred forty-two thousand, two hundred twenty-one".