12021012221 has 4 divisors (see below), whose sum is σ = 12043997472. Its totient is φ = 11998026972.

The previous prime is 12021012193. The next prime is 12021012253. The reversal of 12021012221 is 12221012021.

12021012221 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, and also an emirpimes, since its reverse is a distinct semiprime: 12221012021 = 19 ⋅643211159.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12021012221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12021012196 and 12021012205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12021012821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11491841 + ... + 11492886.

It is an arithmetic number, because the mean of its divisors is an integer number (3010999368).

Almost surely, 2^12021012221 is an apocalyptic number.

It is an amenable number.

12021012221 is a deficient number, since it is larger than the sum of its proper divisors (22985251).

12021012221 is an equidigital number, since it uses as much as digits as its factorization.

12021012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22985250.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 12021012221 its reverse (12221012021), we get a palindrome (24242024242).

The spelling of 12021012221 in words is "twelve billion, twenty-one million, twelve thousand, two hundred twenty-one".