imo you have a pretty decent amount of showdown value being that you have and Ace. The only hand that is going to call you on the river is going to have you beat so by checking behind you can control the size of the pot and lose the min to preserve your stack. If your not prepared to call a raise or a shove from the villian on the river I dont think you should be betting it.

A UTG open with 23 bigs looks realllly strong, so AK is definitely in your range from his point of view.  But at the same time it's most certainly in his range as well since he called your raise with even less chips than you have.  If your bluff isn't successful you're down to like 13 bigs…

I probably fold preflop to be honest, just too many shove stacks to get through and you're not going to feel great calling off most of your chips with A8.

If you were taking this pot is was on the turn, he has some kind  of show down equity and probably is calling 80% of the time + on your river bluff, that being said He's not beating a king here so there a chance to get him to fold but any savy poker player is snap calling you betting the river scare card. Me? I surrender the hand but if you bet it make it Big like 4/5 pot or something.