Possibly a Peruvian Apple Cactus?

[CactiKC774]

Hey all - first time poster and cactus owner. I picked up this guy a few weeks ago at a pop-up large cactus event and I was just trying to nail down what it is. Some casual internet searching has me thinking it's a Peruvian Apple Cactus (Cereus Repandus), but I wanted to do a little more research before I pop one of those fruit off the side and wind up in the hospital haha.

Also looking for any tips on keeping large cacti happy. I've moved it outside now that the summer heat is dying down and it seems to be enjoying it. Within a day of moving it outdoors the fruit started turning that purple color from their original green. This time of year it's usually sunny and mid-70s to low-80s during the day and mid-50s to low-60s at night. I figured I'd bring it in when the temp starts dipping down below 50 at night. It's in a fast-draining cactus soil and I'm giving it a cup of water every month.

Appreciate any feedback. Thanks.