AK big stack... against reraise utg big stack too

[inforrtel]

PokerStars No-Limit Hold'em Tourney, Big Blind is t600 (9 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

UTG+1 (t22495)
MP1 (t16905)
MP2 (t20836)
MP3 (t14783)
CO (t3320)
Button (t7660)
Hero (t33862)
BB (t3992)
UTG (t7490)

Preflop: Hero is SB with K, A.
1 fold, UTG+1 raises to t1445, 5 folds, Hero raises to t3600, 1 fold, UTG+1 raises to t12500, Hero ????

vilain is very LAG... last round he gonna all in PF with AJo and double up
I put he in 88+ or AJ+
should I push or fold?

And if I'm sure its a flip?