21211123321 has 2 divisors, whose sum is σ = 21211123322. Its totient is φ = 21211123320.

The previous prime is 21211123301. The next prime is 21211123327. The reversal of 21211123321 is 12332111212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18302031225 + 2909092096 = 135285^2 + 53936^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211123321 - 2⁵ = 21211123289 is a prime.

It is not a weakly prime, because it can be changed into another prime (21211123327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605561660 + 10605561661.

It is an arithmetic number, because the mean of its divisors is an integer number (10605561661).

Almost surely, 2^21211123321 is an apocalyptic number.

It is an amenable number.

21211123321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211123321 is an equidigital number, since it uses as much as digits as its factorization.

21211123321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 144, while the sum is 19.

Adding to 21211123321 its reverse (12332111212), we get a palindrome (33543234533).

The spelling of 21211123321 in words is "twenty-one billion, two hundred eleven million, one hundred twenty-three thousand, three hundred twenty-one".