12221212111 has 4 divisors (see below), whose sum is σ = 12223555432. Its totient is φ = 12218868792.

The previous prime is 12221212109. The next prime is 12221212169. The reversal of 12221212111 is 11121212221.

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 12221212111 - 2¹ = 12221212109 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 (12221312111) 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 3 ways as a sum of consecutive naturals, for example, 1163820 + ... + 1174273.

It is an arithmetic number, because the mean of its divisors is an integer number (3055888858).

Almost surely, 2^12221212111 is an apocalyptic number.

12221212111 is a deficient number, since it is larger than the sum of its proper divisors (2343321).

12221212111 is an equidigital number, since it uses as much as digits as its factorization.

12221212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2343320.

The product of its digits is 32, while the sum is 16.

Adding to 12221212111 its reverse (11121212221), we get a palindrome (23342424332).

The spelling of 12221212111 in words is "twelve billion, two hundred twenty-one million, two hundred twelve thousand, one hundred eleven".