11221221211 has 4 divisors (see below), whose sum is σ = 11257072072. Its totient is φ = 11185370352.

The previous prime is 11221221113. The next prime is 11221221217. The reversal of 11221221211 is 11212212211.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11221221211 - 2²⁷ = 11087003483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11221221217) 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, 17924961 + ... + 17925586.

It is an arithmetic number, because the mean of its divisors is an integer number (2814268018).

Almost surely, 2^11221221211 is an apocalyptic number.

11221221211 is a deficient number, since it is larger than the sum of its proper divisors (35850861).

11221221211 is an equidigital number, since it uses as much as digits as its factorization.

11221221211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35850860.

The product of its digits is 32, while the sum is 16.

Adding to 11221221211 its reverse (11212212211), we get a palindrome (22433433422).

The spelling of 11221221211 in words is "eleven billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred eleven".