11222211221 has 16 divisors (see below), whose sum is σ = 12733383936. Its totient is φ = 9812347776.

The previous prime is 11222211199. The next prime is 11222211239. The reversal of 11222211221 is 12211222211.

It is a cyclic number.

It is not a de Polignac number, because 11222211221 - 2⁶ = 11222211157 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11222211221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11222217221) 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, 151400 + ... + 212993.

It is an arithmetic number, because the mean of its divisors is an integer number (795836496).

Almost surely, 2^11222211221 is an apocalyptic number.

It is an amenable number.

11222211221 is a deficient number, since it is larger than the sum of its proper divisors (1511172715).

11222211221 is a wasteful number, since it uses less digits than its factorization.

11222211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364532.

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

Adding to 11222211221 its reverse (12211222211), we get a palindrome (23433433432).

The spelling of 11222211221 in words is "eleven billion, two hundred twenty-two million, two hundred eleven thousand, two hundred twenty-one".