12211101212221 has 4 divisors (see below), whose sum is σ = 12211111522012. Its totient is φ = 12211090902432.

The previous prime is 12211101212179. The next prime is 12211101212231. The reversal of 12211101212221 is 12221210111221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 6079232672100 + 6131868540121 = 2465610^2 + 2476261^2 .

It is a cyclic number.

It is not a de Polignac number, because 12211101212221 - 2²¹ = 12211099115069 is a prime.

It is a super-2 number, since 2×12211101212221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12211101212231) 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, 3107106 + ... + 5837491.

It is an arithmetic number, because the mean of its divisors is an integer number (3052777880503).

Almost surely, 2^{12211101212221} is an apocalyptic number.

It is an amenable number.

12211101212221 is a deficient number, since it is larger than the sum of its proper divisors (10309791).

12211101212221 is an equidigital number, since it uses as much as digits as its factorization.

12211101212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10309790.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 12211101212221 its reverse (12221210111221), we get a palindrome (24432311323442).

The spelling of 12211101212221 in words is "twelve trillion, two hundred eleven billion, one hundred one million, two hundred twelve thousand, two hundred twenty-one".