عَنْ أَبِي هُرَيْرَةَ، قَالَ (قال النبي صلّى اللّٰه عليه وسلّم (لِلّٰه تِسْعَةٌ وَتِسْعُونَ اسْمًا، مِائَةٌ إِلاَّ وَاحِدًا، لاَ يَحْفَظُهَا أَحَدٌ إِلاَّ دَخَلَ الْجَنَّةَ، وَهْوَ وَتْرٌ يُحِبُّ الْوَتْرَ.
Hazrat Abu Hurairahra narrated that [the Holy Prophetsa] said, “Allah has ninety-nine names, meaning one less than a hundred. Whoever memorises them will surely enter Paradise. And Allah is witr [i.e., One, Unique and odd-numbered] and loves what is odd-numbered.”
(Sahih al-Bukhari, Kitab as-da‘wat, Bab lillahi mi’ata ismin ghayra wahid, Hadith 6410)