Asking my ex to prom?

A brief introduction to our relationship, my ex and I dated for about 6 months when he broke up with me. We broke up amicably (a little awkwardly but it was fine) and we’ve been pretty courteous to each other. For about 3-4 months, hes made an effort to talk to me and I appreciate the invitation to be better friends and it’s been great! We talked a lot and we’ve gotten closer now that we’ve changed and grown a bit. We’re comfortable being alone together and we’re great friends.. Sooo here’s the dilemma, no one has asked me to prom and my ex hasn’t asked anyone either so I got the bright idea to ask him if he wanted to go with me. I’m not necessarily looking for a romantic relationship with him but if it happens, it happens. I’m not afraid of rejection because he’s a nice person and rejection isn’t really that bad for me. I’m just wondering if maybe it would be too awkward to ask him? What do y’all think?