12211212221221 has 8 divisors (see below), whose sum is σ = 13273438447584. Its totient is φ = 11166543453360.

The previous prime is 12211212221213. The next prime is 12211212221227. The reversal of 12211212221221 is 12212221211221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12211212221221 - 2³ = 12211212221213 is a prime.

It is a super-2 number, since 2×12211212221221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12211212221192 and 12211212221201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12211212221227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4389363175 + ... + 4389365956.

It is an arithmetic number, because the mean of its divisors is an integer number (1659179805948).

Almost surely, 2^{12211212221221} is an apocalyptic number.

It is an amenable number.

12211212221221 is a deficient number, since it is larger than the sum of its proper divisors (1062226226363).

12211212221221 is a wasteful number, since it uses less digits than its factorization.

12211212221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8778729251.

The product of its digits is 256, while the sum is 22.

Adding to 12211212221221 its reverse (12212221211221), we get a palindrome (24423433432442).

The spelling of 12211212221221 in words is "twelve trillion, two hundred eleven billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-one".