The Messenger of Allah said to me: 'When you perform ablution, clean your nose, and when you use pebbles to clean yourself after defecating, use an odd number.'" (Using translation from Ibn Mājah 406)
قَالَ رَسُولُ اللهِ ﷺ «إِذَا تَوَضَّأْتَ فَاسْتَنْثِرْ وَإِذَا اسْتَجْمَرْتَ فَأَوْتِرْ»