11122211221 has 12 divisors (see below), whose sum is σ = 12227794432. Its totient is φ = 10108989000.

The previous prime is 11122211209. The next prime is 11122211227. The reversal of 11122211221 is 12211222111.

It is not a de Polignac number, because 11122211221 - 2¹¹ = 11122209173 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11122211195 and 11122211204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11122211227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1094956 + ... + 1105066.

Almost surely, 2^11122211221 is an apocalyptic number.

11122211221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11122211221 is a deficient number, since it is larger than the sum of its proper divisors (1105583211).

11122211221 is a wasteful number, since it uses less digits than its factorization.

11122211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19224 (or 19213 counting only the distinct ones).

The product of its digits is 32, while the sum is 16.

Adding to 11122211221 its reverse (12211222111), we get a palindrome (23333433332).

The spelling of 11122211221 in words is "eleven billion, one hundred twenty-two million, two hundred eleven thousand, two hundred twenty-one".