11121212111 has 4 divisors (see below), whose sum is σ = 11231323224. Its totient is φ = 11011101000.

The previous prime is 11121211987. The next prime is 11121212153.

11121212111 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11121212111 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 (11121215111) 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, 55055405 + ... + 55055606.

It is an arithmetic number, because the mean of its divisors is an integer number (2807830806).

Almost surely, 2^11121212111 is an apocalyptic number.

11121212111 is a deficient number, since it is larger than the sum of its proper divisors (110111113).

11121212111 is a wasteful number, since it uses less digits than its factorization.

11121212111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110111112.

The product of its digits is 8, while the sum is 14.

The spelling of 11121212111 in words is "eleven billion, one hundred twenty-one million, two hundred twelve thousand, one hundred eleven".