22112221 has 2 divisors, whose sum is σ = 22112222. Its totient is φ = 22112220.

The previous prime is 22112213. The next prime is 22112249. The reversal of 22112221 is 12221122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15912121 + 6200100 = 3989^2 + 2490^2 .

It is a cyclic number.

It is not a de Polignac number, because 22112221 - 2³ = 22112213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22112201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11056110 + 11056111.

It is an arithmetic number, because the mean of its divisors is an integer number (11056111).

Almost surely, 2^22112221 is an apocalyptic number.

It is an amenable number.

22112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

22112221 is an equidigital number, since it uses as much as digits as its factorization.

22112221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32, while the sum is 13.

The square root of 22112221 is about 4702.3633419803. The cubic root of 22112221 is about 280.6795611029.

Adding to 22112221 its reverse (12221122), we get a palindrome (34333343).

The spelling of 22112221 in words is "twenty-two million, one hundred twelve thousand, two hundred twenty-one".