What is the name of last abbasi khalifa?

The last Abbasid caliph was Al-Mustakfi Billah, who ruled from 1517 until the fall of the Abbasid Caliphate after the Ottoman conquest of Baghdad. Following this event, the Abbasid title continued in a nominal sense under Ottoman protection, but the political power of the caliphate effectively ended. The Abbasid lineage persists in a cultural and historical context, but Al-Mustakfi is generally recognized as the final caliph of the Abbasid dynasty.