21322230221 has 2 divisors, whose sum is σ = 21322230222. Its totient is φ = 21322230220.

The previous prime is 21322230151. The next prime is 21322230233. The reversal of 21322230221 is 12203222312.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11233032196 + 10089198025 = 105986^2 + 100445^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21322230221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21322230193 and 21322230202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21322230821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661115110 + 10661115111.

It is an arithmetic number, because the mean of its divisors is an integer number (10661115111).

Almost surely, 2^21322230221 is an apocalyptic number.

It is an amenable number.

21322230221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21322230221 is an equidigital number, since it uses as much as digits as its factorization.

21322230221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21322230221 its reverse (12203222312), we get a palindrome (33525452533).

The spelling of 21322230221 in words is "twenty-one billion, three hundred twenty-two million, two hundred thirty thousand, two hundred twenty-one".