How do social media apps detect VOIP numbers?

My partners and me create a mass of accounts every day at large social media apps like Instagram, TikTok, Snapchat, Tinder, Kik and others. So we always need fresh mobile numbers to verify the accounts by SMS. We use automated account creator bots, so the manual work of the verification process has to be reduced as much as possible.

My question: How do social media apps detect if the number you entered is a real (physical) mobile number or a VOIP number? Is there any public directory like the RIPE IP database or the .com domain register?

I mean, normally the number providers don't show a list of available numbers, to be scraped by the app owners. And I doubt that they send their number base to Instagram, Tinder & Co.

I would love to read your suggestions, my goal is to bypass their VOIP detection sooner or later automatically.