Imam Bukhari narrates: Shu'aib said: And Nafi' narrated to me from Abdullah bin Umar, may Allāh be pleased with them both, that
prayer in congregation has a superiority of twenty-seven degrees over prayer alone.
قَالَ شُعَيْبٌ: وَحَدَّثَنِي نَافِعٌ عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، قَالَ: «تَفْضُلُهَا بِسَبْعٍ وَعِشْرِينَ دَرَجَةً»
Reference: Sahih Al Bukhari 649