1222112221 has 16 divisors (see below), whose sum is σ = 1357690176. Its totient is φ = 1099890000.

The previous prime is 1222112219. The next prime is 1222112239.

It is a happy number.

1222112221 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1222112221 - 2¹ = 1222112219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1222112195 and 1222112204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222112621) 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, 129886 + ... + 138976.

It is an arithmetic number, because the mean of its divisors is an integer number (84855636).

Almost surely, 2^1222112221 is an apocalyptic number.

1222112221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1222112221 is a deficient number, since it is larger than the sum of its proper divisors (135577955).

1222112221 is an equidigital number, since it uses as much as digits as its factorization.

1222112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9225 (or 9203 counting only the distinct ones).

The product of its digits is 64, while the sum is 16.

The square root of 1222112221 is about 34958.7216728530. The cubic root of 1222112221 is about 1069.1460333366.

It can be divided in two parts, 12221 and 12221, that added together give a palindrome (24442).

The spelling of 1222112221 in words is "one billion, two hundred twenty-two million, one hundred twelve thousand, two hundred twenty-one".