According to https://nuclearsecrecy.com/nukemap/ - it'd take at least a 1 megaton warhead to take out two of the ap-southeast-2 datacenters, and over 10MT to take out 3.
I suspect you'd need a lot less than that though, the 1MT warhead would probably take out enough outside-the-datacenter infrastructure to take the entire AZ offline. I don't care too much though, if someone's dropped a warhead that close to home I have other things to worry about than whether all the cat pictures and audit logs survive.