21022213321 has 2 divisors, whose sum is σ = 21022213322. Its totient is φ = 21022213320.

The previous prime is 21022213319. The next prime is 21022213327. The reversal of 21022213321 is 12331222012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21007313721 + 14899600 = 144939^2 + 3860^2 .

It is a cyclic number.

It is not a de Polignac number, because 21022213321 - 2¹ = 21022213319 is a prime.

Together with 21022213319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21022213327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511106660 + 10511106661.

It is an arithmetic number, because the mean of its divisors is an integer number (10511106661).

Almost surely, 2^21022213321 is an apocalyptic number.

It is an amenable number.

21022213321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022213321 is an equidigital number, since it uses as much as digits as its factorization.

21022213321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21022213321 its reverse (12331222012), we get a palindrome (33353435333).

The spelling of 21022213321 in words is "twenty-one billion, twenty-two million, two hundred thirteen thousand, three hundred twenty-one".