21021300320221 has 2 divisors, whose sum is σ = 21021300320222. Its totient is φ = 21021300320220.

The previous prime is 21021300320219. The next prime is 21021300320249. The reversal of 21021300320221 is 12202300312012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20948608611225 + 72691708996 = 4576965^2 + 269614^2 .

It is a cyclic number.

It is not a de Polignac number, because 21021300320221 - 2¹ = 21021300320219 is a prime.

Together with 21021300320219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21021300320281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510650160110 + 10510650160111.

It is an arithmetic number, because the mean of its divisors is an integer number (10510650160111).

Almost surely, 2^{21021300320221} is an apocalyptic number.

It is an amenable number.

21021300320221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021300320221 is an equidigital number, since it uses as much as digits as its factorization.

21021300320221 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 21021300320221 its reverse (12202300312012), we get a palindrome (33223600632233).

The spelling of 21021300320221 in words is "twenty-one trillion, twenty-one billion, three hundred million, three hundred twenty thousand, two hundred twenty-one".