12225221 has 2 divisors, whose sum is σ = 12225222. Its totient is φ = 12225220.

The previous prime is 12225209. The next prime is 12225223. The reversal of 12225221 is 12252221.

12225221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7756225 + 4468996 = 2785^2 + 2114^2 .

It is a cyclic number.

It is not a de Polignac number, because 12225221 - 2²² = 8030917 is a prime.

It is a Sophie Germain prime.

Together with 12225223, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 12225221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12225223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6112610 + 6112611.

It is an arithmetic number, because the mean of its divisors is an integer number (6112611).

Almost surely, 2^12225221 is an apocalyptic number.

It is an amenable number.

12225221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12225221 is an equidigital number, since it uses as much as digits as its factorization.

12225221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 160, while the sum is 17.

The square root of 12225221 is about 3496.4583509603. The cubic root of 12225221 is about 230.3662783904.

Adding to 12225221 its reverse (12252221), we get a palindrome (24477442).

Subtracting 12225221 from its reverse (12252221), we obtain a cube (27000 = 30³).

It can be divided in two parts, 1 and 2225221, that added together give a palindrome (2225222).

The spelling of 12225221 in words is "twelve million, two hundred twenty-five thousand, two hundred twenty-one".