Write a program to compute all proper factors of the input number.

The output should be an ordered sequence of divisors of the input along with an indicator if they are prime or not, with largest divisor first. 

A divisor and its indicator should be enclosed in braces.

For example, on input 42, the output is (21 0) (14 0) (7 1) (6 0) (3 1) (2 1). 
On input 16, the output is (8 0) (4 0) (2 1), etc.