12112211221 has 16 divisors (see below), whose sum is σ = 14441891328. Its totient is φ = 10029081600.

The previous prime is 12112211213. The next prime is 12112211227. The reversal of 12112211221 is 12211221121.

It is a cyclic number.

It is not a de Polignac number, because 12112211221 - 2³ = 12112211213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12112211195 and 12112211204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12112211227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1038900 + ... + 1050493.

It is an arithmetic number, because the mean of its divisors is an integer number (902618208).

Almost surely, 2^12112211221 is an apocalyptic number.

12112211221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12112211221 is a deficient number, since it is larger than the sum of its proper divisors (2329680107).

12112211221 is a wasteful number, since it uses less digits than its factorization.

12112211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2089452.

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

Adding to 12112211221 its reverse (12211221121), we get a palindrome (24323432342).

It can be divided in two parts, 121 and 12211221, that multiplied together give a palindrome (1477557741).

The spelling of 12112211221 in words is "twelve billion, one hundred twelve million, two hundred eleven thousand, two hundred twenty-one".