It is undesirable (Makruh) to touch the penis and to clean oneself from the call of nature with the right hand
حَدَّثَنَا عَلِيُّ بْنُ مُحَمَّدٍ، حَدَّثَنَا وَكِيعٌ، حَدَّثَنَا الصَّلْتُ بْنُ دِينَارٍ، عَنْ عُقْبَةَ بْنِ صُهْبَانَ، قَالَ سَمِعْتُ عُثْمَانَ بْنَ عَفَّانَ، يَقُولُ مَا تَغَنَّيْتُ وَلاَ تَمَنَّيْتُ وَلاَ مَسِسْتُ ذَكَرِي بِيَمِينِي مُنْذُ بَايَعْتُ بِهَا رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ .
It was narrated that 'Uqbah bin Suhban said: "I heard 'Uthman bin 'Affan say: 'I never sang a song or told a lie or touched my penis with my right hand after I swore on oath of allegiance to the Messenger of Allah (ﷺ) to that effect.'"