11221120021 has 2 divisors, whose sum is σ = 11221120022. Its totient is φ = 11221120020.

The previous prime is 11221120019. The next prime is 11221120033. The reversal of 11221120021 is 12002112211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8381402500 + 2839717521 = 91550^2 + 53289^2 .

It is a cyclic number.

It is not a de Polignac number, because 11221120021 - 2¹ = 11221120019 is a prime.

Together with 11221120019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 11221119983 and 11221120010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11221120051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5610560010 + 5610560011.

It is an arithmetic number, because the mean of its divisors is an integer number (5610560011).

Almost surely, 2^11221120021 is an apocalyptic number.

It is an amenable number.

11221120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11221120021 is an equidigital number, since it uses as much as digits as its factorization.

11221120021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 11221120021 its reverse (12002112211), we get a palindrome (23223232232).

The spelling of 11221120021 in words is "eleven billion, two hundred twenty-one million, one hundred twenty thousand, twenty-one".