Look at the picture attached down here. You can see the Venn Diagram fully completed. As you can see the brown part is the empty loop. And this is because the list of numbers given do not share 4 and 9 (6 excluded) as common multiples.
The numbers outside the circles are numbers that are not multiples of 4 or 9 or 6. It's 371 and 79. By the way, 79 is a prime number, so it's only divisors are itself and 1. 371 is not a prime number, it is divisible by 1, 7, 53, 371.
Good luck
