11111211111 has 96 divisors (see below), whose sum is σ = 20586033664. Its totient is φ = 5183481600.

The previous prime is 11111211073. The next prime is 11111211121.

11111211111 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 11111211111 - 2⁷ = 11111210983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111211121) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1217676 + ... + 1226766.

Almost surely, 2^11111211111 is an apocalyptic number.

11111211111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11111211111 is a deficient number, since it is larger than the sum of its proper divisors (9474822553).

11111211111 is a wasteful number, since it uses less digits than its factorization.

11111211111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9173 (or 9162 counting only the distinct ones).

The product of its digits is 2, while the sum is 12.

It can be divided in two parts, 11111 and 211111, that added together give a palindrome (222222).

The spelling of 11111211111 in words is "eleven billion, one hundred eleven million, two hundred eleven thousand, one hundred eleven".