My five-year old added these numbers in his head and I'm not quite sure what to do about it.

At church this morning, my five-year old just pulled my sleeve and said "dad, all together, those numbers make 384."

And then he went back playing with his Legos

I thought it was one of those stupid things kids say, but he sounded so confident, so I added them on my phone and I'll be darned. He was right.

I quite honestly don't know what to think. He's always liked numbers and will randomly say things like "Dad, there are 16 granola bars in this box, so two boxes would make 32 bars." He says stuff like that frequently, so I know he's crunching numbers up there in his brain. But he's a pretty quiet kid, so I've never given it much thought.

But he's literally a week into kindergarten and although we've always talked at home about numbers, I certainly haven't taught him how to add multiple three-digit numbers in his head.

Are some kids just programmed like this? What advice does anyone have on raising a kid with a brain like that? I am very bad at math and it was always my worst subject in school, so I feel a little out of my depth on what (if anything) I can do to support him.