12109221 has 12 divisors (see below), whose sum is σ = 17863872. Its totient is φ = 7900776.

The previous prime is 12109217. The next prime is 12109231. The reversal of 12109221 is 12290121.

12109221 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12109221 - 2² = 12109217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12109194 and 12109203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12109231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13891 + ... + 14736.

It is an arithmetic number, because the mean of its divisors is an integer number (1488656).

Almost surely, 2^12109221 is an apocalyptic number.

It is an amenable number.

12109221 is a deficient number, since it is larger than the sum of its proper divisors (5754651).

12109221 is a wasteful number, since it uses less digits than its factorization.

12109221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28680 (or 28677 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 12109221 is about 3479.8305993252. The cubic root of 12109221 is about 229.6353452872.

Adding to 12109221 its reverse (12290121), we get a palindrome (24399342).

The spelling of 12109221 in words is "twelve million, one hundred nine thousand, two hundred twenty-one".