11222112221 has 4 divisors (see below), whose sum is σ = 11268677244. Its totient is φ = 11175547200.

The previous prime is 11222112211. The next prime is 11222112227. The reversal of 11222112221 is 12221122211.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12221122211 = 4679 ⋅2611909.

It can be written as a sum of positive squares in 2 ways, for example, as 5758684996 + 5463427225 = 75886^2 + 73915^2 .

It is a cyclic number.

It is not a de Polignac number, because 11222112221 - 2⁶ = 11222112157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 11222112221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11222112227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23282150 + ... + 23282631.

It is an arithmetic number, because the mean of its divisors is an integer number (2817169311).

Almost surely, 2^11222112221 is an apocalyptic number.

It is an amenable number.

11222112221 is a deficient number, since it is larger than the sum of its proper divisors (46565023).

11222112221 is an equidigital number, since it uses as much as digits as its factorization.

11222112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46565022.

The product of its digits is 64, while the sum is 17.

Adding to 11222112221 its reverse (12221122211), we get a palindrome (23443234432).

The spelling of 11222112221 in words is "eleven billion, two hundred twenty-two million, one hundred twelve thousand, two hundred twenty-one".