Sūrah No.40, Revealed in Madīnah, 85 verses.
The Sūrah is also known as Sūrat al-Mu’min, as it includes the story of the Mu’min of Āl-i Fir‘awn. His story only appears in this Sūrah. More than 20 verses of the Sūrah – about one fourth of the Sūrah – talks about him.
It is the first of the Hawamīm Sūrahs – those that begin with the letters Hā-Mīm. There are seven of these Sūrahs from Sūrahs no.40-46, in order.
The Sūrah takes its name from verse 3 which refers to Allah X as the Forgiver of sins.
Some believe that though the Sūrah is Makkan, verses 56 and 57 or verses 55-57 were revealed in Madīnah.