12133221 has 4 divisors (see below), whose sum is σ = 16177632. Its totient is φ = 8088812.

The previous prime is 12133217. The next prime is 12133241. The reversal of 12133221 is 12233121.

12133221 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, 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 12133221 - 2² = 12133217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12133221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12133241) 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, 2022201 + ... + 2022206.

It is an arithmetic number, because the mean of its divisors is an integer number (4044408).

Almost surely, 2^12133221 is an apocalyptic number.

It is an amenable number.

12133221 is a deficient number, since it is larger than the sum of its proper divisors (4044411).

12133221 is an equidigital number, since it uses as much as digits as its factorization.

12133221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4044410.

The product of its digits is 72, while the sum is 15.

The square root of 12133221 is about 3483.2773360730. The cubic root of 12133221 is about 229.7869545791.

Adding to 12133221 its reverse (12233121), we get a palindrome (24366342).

The spelling of 12133221 in words is "twelve million, one hundred thirty-three thousand, two hundred twenty-one".