11122111212221 has 4 divisors (see below), whose sum is σ = 11776353048252. Its totient is φ = 10467869376192.

The previous prime is 11122111212197. The next prime is 11122111212227. The reversal of 11122111212221 is 12221211122111.

It is a happy number.

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 6780743088196 + 4341368124025 = 2603986^2 + 2083595^2 .

It is a cyclic number.

It is not a de Polignac number, because 11122111212221 - 2¹⁸ = 11122110950077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11122111212193 and 11122111212202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11122111212227) 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, 327120917990 + ... + 327120918023.

It is an arithmetic number, because the mean of its divisors is an integer number (2944088262063).

Almost surely, 2^{11122111212221} is an apocalyptic number.

It is an amenable number.

11122111212221 is a deficient number, since it is larger than the sum of its proper divisors (654241836031).

11122111212221 is an equidigital number, since it uses as much as digits as its factorization.

11122111212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654241836030.

The product of its digits is 64, while the sum is 20.

Adding to 11122111212221 its reverse (12221211122111), we get a palindrome (23343322334332).

The spelling of 11122111212221 in words is "eleven trillion, one hundred twenty-two billion, one hundred eleven million, two hundred twelve thousand, two hundred twenty-one".