Google tells me you're the one who has them backwards. Here's an article from Carnegie Natural History Museum explaining the difference.

it's extremely obvious that you're incorrect if you simply look at the words, "centi" means "hundred" and is smaller than "milli" which means "thousand".

centipedes look like they have a hundred legs, millipedes look like they have a thousand legs.

"Centipede" means 100 feet.

"Millipede" means 1000 feet.