It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both), he says: According to our count, the Messenger of Allah (peace and blessings be upon him) would recite this supplication one hundred times in a single gathering: "Rabbighfir li wa tub 'alayya, innaka anta at-Tawwab al-Ghafur" (O my Lord! Forgive me and accept my repentance, surely You are the Acceptor of Repentance, the Most Forgiving).