11111211211111 has 16 divisors (see below), whose sum is σ = 12150375736320. Its totient is φ = 10076918057920.

The previous prime is 11111211211063. The next prime is 11111211211153.

11111211211111 is nontrivially palindromic in base 10.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111211211111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111211211181) 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, 6956436 + ... + 8403238.

It is an arithmetic number, because the mean of its divisors is an integer number (759398483520).

Almost surely, 2^{11111211211111} is an apocalyptic number.

11111211211111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11111211211111 is a deficient number, since it is larger than the sum of its proper divisors (1039164525209).

11111211211111 is a wasteful number, since it uses less digits than its factorization.

11111211211111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1448486.

The product of its digits is 4, while the sum is 16.

It can be divided in two parts, 1111121 and 1211111, that added together give a palindrome (2322232).

The spelling of 11111211211111 in words is "eleven trillion, one hundred eleven billion, two hundred eleven million, two hundred eleven thousand, one hundred eleven".