12201211221 has 4 divisors (see below), whose sum is σ = 16268281632. Its totient is φ = 8134140812.

The previous prime is 12201211199. The next prime is 12201211237. The reversal of 12201211221 is 12211210221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12201211221 - 2¹³ = 12201203029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12201211221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12201211721) 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, 2033535201 + ... + 2033535206.

It is an arithmetic number, because the mean of its divisors is an integer number (4067070408).

Almost surely, 2^12201211221 is an apocalyptic number.

It is an amenable number.

12201211221 is a deficient number, since it is larger than the sum of its proper divisors (4067070411).

12201211221 is an equidigital number, since it uses as much as digits as its factorization.

12201211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4067070410.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 12201211221 its reverse (12211210221), we get a palindrome (24412421442).

The spelling of 12201211221 in words is "twelve billion, two hundred one million, two hundred eleven thousand, two hundred twenty-one".