11122221222221 has 4 divisors (see below), whose sum is σ = 11122613554944. Its totient is φ = 11121828889500.

The previous prime is 11122221222191. The next prime is 11122221222241. The reversal of 11122221222221 is 12222212222111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11122221222221 - 2¹⁸ = 11122220960077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11122221222241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196123835 + ... + 196180536.

It is an arithmetic number, because the mean of its divisors is an integer number (2780653388736).

Almost surely, 2^{11122221222221} is an apocalyptic number.

It is an amenable number.

11122221222221 is a deficient number, since it is larger than the sum of its proper divisors (392332723).

11122221222221 is an equidigital number, since it uses as much as digits as its factorization.

11122221222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392332722.

The product of its digits is 512, while the sum is 23.

Adding to 11122221222221 its reverse (12222212222111), we get a palindrome (23344433444332).

The spelling of 11122221222221 in words is "eleven trillion, one hundred twenty-two billion, two hundred twenty-one million, two hundred twenty-two thousand, two hundred twenty-one".