1222111221 has 16 divisors (see below), whose sum is σ = 1686718464. Its totient is φ = 786469824.

The previous prime is 1222111207. The next prime is 1222111273. The reversal of 1222111221 is 1221112221.

It is not a de Polignac number, because 1222111221 - 2⁶ = 1222111157 is a prime.

It is a super-2 number, since 2×1222111221² = 2987111672988221682, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1222111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222111201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29250 + ... + 57443.

It is an arithmetic number, because the mean of its divisors is an integer number (105419904).

Almost surely, 2^1222111221 is an apocalyptic number.

It is an amenable number.

1222111221 is a deficient number, since it is larger than the sum of its proper divisors (464607243).

1222111221 is a wasteful number, since it uses less digits than its factorization.

1222111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86860.

The product of its digits is 32, while the sum is 15.

The square root of 1222111221 is about 34958.7073702676. The cubic root of 1222111221 is about 1069.1457417250.

Adding to 1222111221 its reverse (1221112221), we get a palindrome (2443223442).

It can be divided in two parts, 1 and 222111221, that added together give a palindrome (222111222).

The spelling of 1222111221 in words is "one billion, two hundred twenty-two million, one hundred eleven thousand, two hundred twenty-one".