21021201000221 has 2 divisors, whose sum is σ = 21021201000222. Its totient is φ = 21021201000220.

The previous prime is 21021201000131. The next prime is 21021201000257. The reversal of 21021201000221 is 12200010212012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12518080848100 + 8503120152121 = 3538090^2 + 2916011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21021201000221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021201000196 and 21021201000205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21021201000271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510600500110 + 10510600500111.

It is an arithmetic number, because the mean of its divisors is an integer number (10510600500111).

Almost surely, 2^{21021201000221} is an apocalyptic number.

It is an amenable number.

21021201000221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021201000221 is an equidigital number, since it uses as much as digits as its factorization.

21021201000221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21021201000221 its reverse (12200010212012), we get a palindrome (33221211212233).

The spelling of 21021201000221 in words is "twenty-one trillion, twenty-one billion, two hundred one million, two hundred twenty-one", and thus it is an aban number.