12201212221 has 16 divisors (see below), whose sum is σ = 13881466368. Its totient is φ = 10623513600.

The previous prime is 12201212209. The next prime is 12201212227. The reversal of 12201212221 is 12221210221.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 12201212221 - 2⁹ = 12201211709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12201212195 and 12201212204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12201212227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151360 + ... + 217513.

It is an arithmetic number, because the mean of its divisors is an integer number (867591648).

Almost surely, 2^12201212221 is an apocalyptic number.

12201212221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12201212221 is a deficient number, since it is larger than the sum of its proper divisors (1680254147).

12201212221 is a wasteful number, since it uses less digits than its factorization.

12201212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369012.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 12201212221 its reverse (12221210221), we get a palindrome (24422422442).

It can be divided in two parts, 12201 and 212221, that added together give a palindrome (224422).

The spelling of 12201212221 in words is "twelve billion, two hundred one million, two hundred twelve thousand, two hundred twenty-one".