221211222217 has 2 divisors, whose sum is σ = 221211222218. Its totient is φ = 221211222216.

The previous prime is 221211222179. The next prime is 221211222223. The reversal of 221211222217 is 712222112122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 126578696841 + 94632525376 = 355779^2 + 307624^2 .

It is a cyclic number.

It is not a de Polignac number, because 221211222217 - 2²³ = 221202833609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221211222191 and 221211222200.

It is not a weakly prime, because it can be changed into another prime (221211222227) 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, 110605611108 + 110605611109.

It is an arithmetic number, because the mean of its divisors is an integer number (110605611109).

Almost surely, 2^221211222217 is an apocalyptic number.

It is an amenable number.

221211222217 is a deficient number, since it is larger than the sum of its proper divisors (1).

221211222217 is an equidigital number, since it uses as much as digits as its factorization.

221211222217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 896, while the sum is 25.

Adding to 221211222217 its reverse (712222112122), we get a palindrome (933433334339).

The spelling of 221211222217 in words is "two hundred twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, two hundred seventeen".