How does a company detect the difference between Datacenter and Residential IP?

I want to know how a company detect if you are running a datacenter ip or a residential ip.

Do they have a list of all datacenters in the world ? ( small and big ones )

what if i take a very little unknown datacenter which newly started to sell IPS, is a company able to detect if its a residential ip or an actual datacenter ?

how do they work, do they put all big datacenters on a blacklist or is there a way to detect this automaticly by the way the IP is made ?

I have the option to buy ips from very small unknown datacenters, but what i actually need is a Residential Ip so i want to know if this would also work, its a certain captcha service which detect me always as a bot and i want to avoid this

IP allocations are a matter of public record, so it's trivial to look up any given IP and find the owner's information. Unless the datacenter is somehow running off a residential ISP and subleasing an IP block, it'll always show up as a datacenter.