21201022100017 has 2 divisors, whose sum is σ = 21201022100018. Its totient is φ = 21201022100016.

The previous prime is 21201022099981. The next prime is 21201022100149. The reversal of 21201022100017 is 71000122010212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14252505012001 + 6948517088016 = 3775249^2 + 2636004^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201022100017 - 2¹⁵ = 21201022067249 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21201022099967 and 21201022100003.

It is not a weakly prime, because it can be changed into another prime (21201022100917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600511050008 + 10600511050009.

It is an arithmetic number, because the mean of its divisors is an integer number (10600511050009).

Almost surely, 2^{21201022100017} is an apocalyptic number.

It is an amenable number.

21201022100017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201022100017 is an equidigital number, since it uses as much as digits as its factorization.

21201022100017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 19.

Adding to 21201022100017 its reverse (71000122010212), we get a palindrome (92201144110229).

The spelling of 21201022100017 in words is "twenty-one trillion, two hundred one billion, twenty-two million, one hundred thousand, seventeen".