Two of my cats died last year, one of them was his daughter who made it to nineteen. The other made it to twenty as well. I credit it to lots of touching and grooming, a good diet, fortunate genetics, and brushing their teeth at least weekly.
He lived with my ex for over a year after I got divorced (my roommate had two kitties already and moving in three more was out of the question) and I visited him and my lady cats nearly every day. When his lady cats died last year he dropped weight almost instantly and I thought he was a goner. I moved him out of my ex's house and in with me, figuring it would be just a short time until he died. That was last September. He soon took to my roommate's two kitties. Their companionship and playfulness has given him new life. However, he's still working on gaining back the weight he lost while he was mourning so he's a bit slim.
He runs around at random times like a Fatbat out of hell and aside from the outbreak of white hairs and whiskers you wouldn't guess he's ancient.