11121212222111 has 4 divisors (see below), whose sum is σ = 11121822725712. Its totient is φ = 11120601718512.

The previous prime is 11121212222093. The next prime is 11121212222161. The reversal of 11121212222111 is 11122221212111.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 11121212222111 - 2³⁴ = 11104032352927 is a prime.

It is a super-3 number, since 3×11121212222111³ (a number of 40 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11121212222161) 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, 305224475 + ... + 305260908.

It is an arithmetic number, because the mean of its divisors is an integer number (2780455681428).

Almost surely, 2^{11121212222111} is an apocalyptic number.

11121212222111 is a deficient number, since it is larger than the sum of its proper divisors (610503601).

11121212222111 is an equidigital number, since it uses as much as digits as its factorization.

11121212222111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610503600.

The product of its digits is 64, while the sum is 20.

Adding to 11121212222111 its reverse (11122221212111), we get a palindrome (22243433434222).

The spelling of 11121212222111 in words is "eleven trillion, one hundred twenty-one billion, two hundred twelve million, two hundred twenty-two thousand, one hundred eleven".