12331221 has 8 divisors (see below), whose sum is σ = 18790464. Its totient is φ = 7046400.

The previous prime is 12331219. The next prime is 12331223. The reversal of 12331221 is 12213321.

12331221 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12331219) and next prime (12331223).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12331221 - 2¹ = 12331219 is a prime.

It is a super-2 number, since 2×12331221² = 304118022701682, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12331221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12331223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 293580 + ... + 293621.

It is an arithmetic number, because the mean of its divisors is an integer number (2348808).

Almost surely, 2^12331221 is an apocalyptic number.

It is an amenable number.

12331221 is a deficient number, since it is larger than the sum of its proper divisors (6459243).

12331221 is an equidigital number, since it uses as much as digits as its factorization.

12331221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 587211.

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

The square root of 12331221 is about 3511.5838306952. The cubic root of 12331221 is about 231.0301679083.

Adding to 12331221 its reverse (12213321), we get a palindrome (24544542).

The spelling of 12331221 in words is "twelve million, three hundred thirty-one thousand, two hundred twenty-one".