12221311121021 has 4 divisors (see below), whose sum is σ = 12221414819100. Its totient is φ = 12221207422944.

The previous prime is 12221311121011. The next prime is 12221311121069. The reversal of 12221311121021 is 12012111312221.

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 4928448840121 + 7292862280900 = 2220011^2 + 2700530^2 .

It is a cyclic number.

It is not a de Polignac number, because 12221311121021 - 2¹⁸ = 12221310858877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12221311120984 and 12221311121002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221311121011) 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, 51672056 + ... + 51908033.

It is an arithmetic number, because the mean of its divisors is an integer number (3055353704775).

Almost surely, 2^{12221311121021} is an apocalyptic number.

It is an amenable number.

12221311121021 is a deficient number, since it is larger than the sum of its proper divisors (103698079).

12221311121021 is a wasteful number, since it uses less digits than its factorization.

12221311121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103698078.

The product of its (nonzero) digits is 96, while the sum is 20.

Adding to 12221311121021 its reverse (12012111312221), we get a palindrome (24233422433242).

The spelling of 12221311121021 in words is "twelve trillion, two hundred twenty-one billion, three hundred eleven million, one hundred twenty-one thousand, twenty-one".