Anyone know what this bump is on cat's tummy

[ncforcatquestion]

He was shaved for a scan, and the vet hasn't mentioned it so I'm assuming it's something harmless. But has anyone seen this before ? Between his nipples there's a raised red bump, no scratches or wound around it

Hernia repair? Have you had him from a baby?

I've had him since he was 6 weeks old and the seller never mentioned anything

Hard to tell but could it be his belly button?

Oh I never thought about that

Yes it's the only thing there that could be a belly button. I think I forgot he would have one of those