I think 2 cats is the perfect amount. Although cats can live alone, they will be happier if they have a companion. It’s best to adopt 2 cats together who were already bonded. But it strongly depends on the cat. My next door neighbour’s cat was very affectionate towards humans, but despised his own kind and preferred being an only kitty. Can’t say I blame him… I’m not terribly fond of my own kind either!