21220324441 has 2 divisors, whose sum is σ = 21220324442. Its totient is φ = 21220324440.

The previous prime is 21220324427. The next prime is 21220324459. The reversal of 21220324441 is 14442302212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17696714841 + 3523609600 = 133029^2 + 59360^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21220324441 is a prime.

It is not a weakly prime, because it can be changed into another prime (21220324421) 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 as a sum of consecutive naturals, namely, 10610162220 + 10610162221.

It is an arithmetic number, because the mean of its divisors is an integer number (10610162221).

Almost surely, 2^21220324441 is an apocalyptic number.

It is an amenable number.

21220324441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220324441 is an equidigital number, since it uses as much as digits as its factorization.

21220324441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21220324441 its reverse (14442302212), we get a palindrome (35662626653).

The spelling of 21220324441 in words is "twenty-one billion, two hundred twenty million, three hundred twenty-four thousand, four hundred forty-one".