12013221221 has 4 divisors (see below), whose sum is σ = 12216835200. Its totient is φ = 11809607244.

The previous prime is 12013221217. The next prime is 12013221301. The reversal of 12013221221 is 12212231021.

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: 12212231021 = 1789 ⋅6826289.

It is a cyclic number.

It is not a de Polignac number, because 12013221221 - 2² = 12013221217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12013221221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12013421221) 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, 101806901 + ... + 101807018.

It is an arithmetic number, because the mean of its divisors is an integer number (3054208800).

Almost surely, 2^12013221221 is an apocalyptic number.

It is an amenable number.

12013221221 is a deficient number, since it is larger than the sum of its proper divisors (203613979).

12013221221 is an equidigital number, since it uses as much as digits as its factorization.

12013221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203613978.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 12013221221 its reverse (12212231021), we get a palindrome (24225452242).

The spelling of 12013221221 in words is "twelve billion, thirteen million, two hundred twenty-one thousand, two hundred twenty-one".