12221044021 has 4 divisors (see below), whose sum is σ = 12242522700. Its totient is φ = 12199565344.

The previous prime is 12221043977. The next prime is 12221044049. The reversal of 12221044021 is 12044012221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8092981521 + 4128062500 = 89961^2 + 64250^2 .

It is a cyclic number.

It is not a de Polignac number, because 12221044021 - 2⁹ = 12221043509 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 12221044021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221044091) 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, 10738486 + ... + 10739623.

It is an arithmetic number, because the mean of its divisors is an integer number (3060630675).

Almost surely, 2^12221044021 is an apocalyptic number.

It is an amenable number.

12221044021 is a deficient number, since it is larger than the sum of its proper divisors (21478679).

12221044021 is an equidigital number, since it uses as much as digits as its factorization.

12221044021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21478678.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 12221044021 its reverse (12044012221), we get a palindrome (24265056242).

The spelling of 12221044021 in words is "twelve billion, two hundred twenty-one million, forty-four thousand, twenty-one".