12011221 has 4 divisors (see below), whose sum is σ = 12533472. Its totient is φ = 11488972.

The previous prime is 12011213. The next prime is 12011227. The reversal of 12011221 is 12211021.

12011221 is digitally balanced in base 3, 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 12011221 - 2³ = 12011213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12011198 and 12011207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12011227) 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, 261091 + ... + 261136.

It is an arithmetic number, because the mean of its divisors is an integer number (3133368).

Almost surely, 2^12011221 is an apocalyptic number.

It is an amenable number.

12011221 is a deficient number, since it is larger than the sum of its proper divisors (522251).

12011221 is an equidigital number, since it uses as much as digits as its factorization.

12011221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 522250.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 12011221 is about 3465.7208485393. The cubic root of 12011221 is about 229.0141864936.

Adding to 12011221 its reverse (12211021), we get a palindrome (24222242).

The spelling of 12011221 in words is "twelve million, eleven thousand, two hundred twenty-one".