11211011221 has 4 divisors (see below), whose sum is σ = 11211438700. Its totient is φ = 11210583744.

The previous prime is 11211011219. The next prime is 11211011243. The reversal of 11211011221 is 12211011211.

It is a happy number.

11211011221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 552720100 + 10658291121 = 23510^2 + 103239^2 .

It is a cyclic number.

It is not a de Polignac number, because 11211011221 - 2¹ = 11211011219 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 (11211011261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171636 + ... + 227773.

It is an arithmetic number, because the mean of its divisors is an integer number (2802859675).

Almost surely, 2^11211011221 is an apocalyptic number.

It is an amenable number.

11211011221 is a deficient number, since it is larger than the sum of its proper divisors (427479).

11211011221 is an equidigital number, since it uses as much as digits as its factorization.

11211011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 427478.

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

Adding to 11211011221 its reverse (12211011211), we get a palindrome (23422022432).

The spelling of 11211011221 in words is "eleven billion, two hundred eleven million, eleven thousand, two hundred twenty-one".