11222221121 has 4 divisors (see below), whose sum is σ = 11231805744. Its totient is φ = 11212636500.

The previous prime is 11222221103. The next prime is 11222221133. The reversal of 11222221121 is 12112222211.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12112222211 = 23 ⋅526618357.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11222221121 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11222221121.

It is not an unprimeable number, because it can be changed into a prime (11222223121) 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, 4790555 + ... + 4792896.

It is an arithmetic number, because the mean of its divisors is an integer number (2807951436).

Almost surely, 2^11222221121 is an apocalyptic number.

It is an amenable number.

11222221121 is a deficient number, since it is larger than the sum of its proper divisors (9584623).

11222221121 is an equidigital number, since it uses as much as digits as its factorization.

11222221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9584622.

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

Adding to 11222221121 its reverse (12112222211), we get a palindrome (23334443332).

The spelling of 11222221121 in words is "eleven billion, two hundred twenty-two million, two hundred twenty-one thousand, one hundred twenty-one".