221211222 has 16 divisors (see below), whose sum is σ = 443435520. Its totient is φ = 73568232.

The previous prime is 221211209. The next prime is 221211223. The reversal of 221211222 is 222112122.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39358 + ... + 44625.

It is an arithmetic number, because the mean of its divisors is an integer number (27714720).

Almost surely, 2^221211222 is an apocalyptic number.

221211222 is an abundant number, since it is smaller than the sum of its proper divisors (222224298).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221211222 is a wasteful number, since it uses less digits than its factorization.

221211222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84427.

The product of its digits is 64, while the sum is 15.

The square root of 221211222 is about 14873.1712153125. The cubic root of 221211222 is about 604.7869130959.

Adding to 221211222 its reverse (222112122), we get a palindrome (443323344).

The spelling of 221211222 in words is "two hundred twenty-one million, two hundred eleven thousand, two hundred twenty-two".