Hi Danielle, there's just something about those discus ay? Nothing quite like the majestic true king of the aquarium. 6-8 discus is recommended as they feel more comfortable in groups, I believe in the wild they school in rather large groups. In saying that I grew out 5 and they were happy enough. It is best to get as many as you can afford and also what your tank can fit. The more you get the more the pecking order is spread out so if any one discus is getting hassled it won't be so much in a larger school. 10 gallons per adult discus is recommended but you can have a few more if you do daily water changes to keep the water quality at a premium. You can also fit more juveniles in than adult discus so if you have multiple tank syndrome you can always get more now and as they grow move some around. Discus do better on their own and due to the other fish you will have to max at 5 adult discus IMO. You don't need even numbers at all, in fact feng shui suggests 3 goldfish is the ideal lucky amount which is obviously an odd number
Goodluck discus buying