1225022221 has 2 divisors, whose sum is σ = 1225022222. Its totient is φ = 1225022220.

The previous prime is 1225022213. The next prime is 1225022237. The reversal of 1225022221 is 1222205221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1224230121 + 792100 = 34989^2 + 890^2 .

It is a cyclic number.

It is not a de Polignac number, because 1225022221 - 2³ = 1225022213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1225028221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 612511110 + 612511111.

It is an arithmetic number, because the mean of its divisors is an integer number (612511111).

Almost surely, 2^1225022221 is an apocalyptic number.

It is an amenable number.

1225022221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1225022221 is an equidigital number, since it uses as much as digits as its factorization.

1225022221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 1225022221 is about 35000.3174414176. The cubic root of 1225022221 is about 1069.9939502380.

Adding to 1225022221 its reverse (1222205221), we get a palindrome (2447227442).

The spelling of 1225022221 in words is "one billion, two hundred twenty-five million, twenty-two thousand, two hundred twenty-one".