11011221121 has 4 divisors (see below), whose sum is σ = 11074869972. Its totient is φ = 10947572272.

The previous prime is 11011221097. The next prime is 11011221131. The reversal of 11011221121 is 12112211011.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12112211011 = 1657 ⋅7309723.

It can be written as a sum of positive squares in 2 ways, for example, as 6406241521 + 4604979600 = 80039^2 + 67860^2 .

It is a cyclic number.

It is not a de Polignac number, because 11011221121 - 2²³ = 11002832513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11011221131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31824166 + ... + 31824511.

It is an arithmetic number, because the mean of its divisors is an integer number (2768717493).

Almost surely, 2^11011221121 is an apocalyptic number.

It is an amenable number.

11011221121 is a deficient number, since it is larger than the sum of its proper divisors (63648851).

11011221121 is an equidigital number, since it uses as much as digits as its factorization.

11011221121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63648850.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 11011221121 its reverse (12112211011), we get a palindrome (23123432132).

The spelling of 11011221121 in words is "eleven billion, eleven million, two hundred twenty-one thousand, one hundred twenty-one".