It was narrated that Abu Hurairah said: “The Prophet (ﷺ) used to observe I’tikaf for ten days every year. In the year in which he passed away, he observed I’tikaf for twenty days. And the Qur’an would be reviewed with him once every year, but in the year in which he passed away, it was reviewed with him twice.”
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا هَنَّادُ بْنُ السَّرِيِّ، حَدَّثَنَا أَبُو بَكْرِ بْنُ عَيَّاشٍ، عَنْ أَبِي حُصَيْنٍ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ كَانَ النَّبِيُّ ـ صلى الله عليه وسلم ـ يَعْتَكِفُ كُلَّ عَامٍ عَشْرَةَ أَيَّامٍ فَلَمَّا كَانَ الْعَامُ الَّذِي قُبِضَ فِيهِ اعْتَكَفَ عِشْرِينَ يَوْمًا وَكَانَ يُعْرَضُ عَلَيْهِ الْقُرْآنُ فِي كُلِّ عَامٍ مَرَّةً فَلَمَّا كَانَ الْعَامُ الَّذِي قُبِضَ فِيهِ عُرِضَ عَلَيْهِ مَرَّتَيْنِ .
sunnah.com