222212221 has 16 divisors (see below), whose sum is σ = 279796608. Its totient is φ = 171432000.

The previous prime is 222212209. The next prime is 222212233. The reversal of 222212221 is 122212222.

It is an interprime number because it is at equal distance from previous prime (222212209) and next prime (222212233).

It is a cyclic number.

It is not a de Polignac number, because 222212221 - 2²¹ = 220115069 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 222212195 and 222212204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222213221) 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 in 15 ways as a sum of consecutive naturals, for example, 6510 + ... + 22063.

It is an arithmetic number, because the mean of its divisors is an integer number (17487288).

Almost surely, 2^222212221 is an apocalyptic number.

It is an amenable number.

222212221 is a deficient number, since it is larger than the sum of its proper divisors (57584387).

222212221 is a wasteful number, since it uses less digits than its factorization.

222212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28692.

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

The square root of 222212221 is about 14906.7843950330. The cubic root of 222212221 is about 605.6977774276.

Adding to 222212221 its reverse (122212222), we get a palindrome (344424443).

Subtracting from 222212221 its reverse (122212222), we obtain a palindrome (99999999).

It can be divided in two parts, 22221 and 2221, that added together give a palindrome (24442).

The spelling of 222212221 in words is "two hundred twenty-two million, two hundred twelve thousand, two hundred twenty-one".