Imam Bukhari narrates: Abdullah bin Yusuf narrated to us, he said: Imam Malik informed us from Nafi' from Abdullah bin Umar, may Allāh be pleased with them both, that the Messenger of Allāh ﷺ said:
Prayer in congregation is superior to prayer alone by twenty-seven degrees.
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، قَالَ: أَخْبَرَنَا مَالِكٌ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ: أَنَّ رَسُولَ اللَّهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ قَالَ: «صَلاَةُ الجَمَاعَةِ تَفْضُلُ صَلاَةَ الفَذِّ بِسَبْعٍ وَعِشْرِينَ دَرَجَةً»
Reference: Sahih Al Bukhari 645