11131223021 has 2 divisors, whose sum is σ = 11131223022. Its totient is φ = 11131223020.

The previous prime is 11131223009. The next prime is 11131223071. The reversal of 11131223021 is 12032213111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8975478121 + 2155744900 = 94739^2 + 46430^2 .

It is an emirp because it is prime and its reverse (12032213111) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11131223021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11131223071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5565611510 + 5565611511.

It is an arithmetic number, because the mean of its divisors is an integer number (5565611511).

Almost surely, 2^11131223021 is an apocalyptic number.

It is an amenable number.

11131223021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11131223021 is an equidigital number, since it uses as much as digits as its factorization.

11131223021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 11131223021 its reverse (12032213111), we get a palindrome (23163436132).

The spelling of 11131223021 in words is "eleven billion, one hundred thirty-one million, two hundred twenty-three thousand, twenty-one".