17221648217 has 2 divisors, whose sum is σ = 17221648218. Its totient is φ = 17221648216.

The previous prime is 17221648189. The next prime is 17221648247. The reversal of 17221648217 is 71284612271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12165869401 + 5055778816 = 110299^2 + 71104^2 .

It is an emirp because it is prime and its reverse (71284612271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 17221648217 - 2¹⁰ = 17221647193 is a prime.

It is not a weakly prime, because it can be changed into another prime (17221648247) 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, 8610824108 + 8610824109.

It is an arithmetic number, because the mean of its divisors is an integer number (8610824109).

Almost surely, 2^17221648217 is an apocalyptic number.

It is an amenable number.

17221648217 is a deficient number, since it is larger than the sum of its proper divisors (1).

17221648217 is an equidigital number, since it uses as much as digits as its factorization.

17221648217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 75264, while the sum is 41.

The spelling of 17221648217 in words is "seventeen billion, two hundred twenty-one million, six hundred forty-eight thousand, two hundred seventeen".