12123211211 has 4 divisors (see below), whose sum is σ = 12131708232. Its totient is φ = 12114714192.

The previous prime is 12123211169. The next prime is 12123211249. The reversal of 12123211211 is 11211232121.

It is a happy number.

12123211211 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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-12123211211 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12123211211.

It is not an unprimeable number, because it can be changed into a prime (12123211271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4246370 + ... + 4249223.

It is an arithmetic number, because the mean of its divisors is an integer number (3032927058).

Almost surely, 2^12123211211 is an apocalyptic number.

12123211211 is a deficient number, since it is larger than the sum of its proper divisors (8497021).

12123211211 is an equidigital number, since it uses as much as digits as its factorization.

12123211211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8497020.

The product of its digits is 48, while the sum is 17.

Adding to 12123211211 its reverse (11211232121), we get a palindrome (23334443332).

The spelling of 12123211211 in words is "twelve billion, one hundred twenty-three million, two hundred eleven thousand, two hundred eleven".