UB 40+4 - Call huge overbet?

[jong]

Hi all,
Its midway through the multi and i have about 9000 in chips, about 10th place of 75 or so remaining (top 20 itm). I limp in MP with AJo for T200 (had raised alot past few orbits, not a play i standardly make but don't mind doing it occasionally either). Two limpers after me including one big stack, and then BB who has about 6000 min raises to 400, we all obviously call. Flop comes A34 rainbow which looks nice but i'm ready to play cautiously and see what BB does, when he pushes all-in for 5600. Is this an easy fold?