11111221111211 has 16 divisors (see below), whose sum is σ = 12641922115200. Its totient is φ = 9692140257408.

The previous prime is 11111221111201. The next prime is 11111221111241. The reversal of 11111221111211 is 11211112211111.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111221111211 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11111221111211.

It is not an unprimeable number, because it can be changed into a prime (11111221111201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 313522016 + ... + 313557453.

It is an arithmetic number, because the mean of its divisors is an integer number (790120132200).

Almost surely, 2^{11111221111211} is an apocalyptic number.

11111221111211 is a deficient number, since it is larger than the sum of its proper divisors (1530701003989).

11111221111211 is a wasteful number, since it uses less digits than its factorization.

11111221111211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627079558.

The product of its digits is 8, while the sum is 17.

Adding to 11111221111211 its reverse (11211112211111), we get a palindrome (22322333322322).

The spelling of 11111221111211 in words is "eleven trillion, one hundred eleven billion, two hundred twenty-one million, one hundred eleven thousand, two hundred eleven".