222101221 has 4 divisors (see below), whose sum is σ = 222255532. Its totient is φ = 221946912.

The previous prime is 222101207. The next prime is 222101233. The reversal of 222101221 is 122101222.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122101222 = 2 ⋅61050611.

It can be written as a sum of positive squares in 2 ways, for example, as 199204996 + 22896225 = 14114^2 + 4785^2 .

It is a cyclic number.

It is not a de Polignac number, because 222101221 - 2⁵ = 222101189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222101251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74976 + ... + 77881.

It is an arithmetic number, because the mean of its divisors is an integer number (55563883).

Almost surely, 2^222101221 is an apocalyptic number.

It is an amenable number.

222101221 is a deficient number, since it is larger than the sum of its proper divisors (154311).

222101221 is a wasteful number, since it uses less digits than its factorization.

222101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154310.

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

The square root of 222101221 is about 14903.0607930049. The cubic root of 222101221 is about 605.5969074113.

Adding to 222101221 its reverse (122101222), we get a palindrome (344202443).

Subtracting from 222101221 its reverse (122101222), we obtain a palindrome (99999999).

The spelling of 222101221 in words is "two hundred twenty-two million, one hundred one thousand, two hundred twenty-one".