Shiny: 1/8192 regular; 1/2048 for masuda method
Pokerus: 3/65,536 chance of getting it on a wild or newly hatched poke
Max Iv's: 1/28629151 (gawd!) and if you are thinking about breeding look at this.
GRAND TOTAL: 1/5131203802551637 chance of getting shiny, pokerus, and perfect iv's.