أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ صَلاَةُ الْجَمَاعَةِ تَفْضُلُ عَلَى صَلاَةِ الْفَذِّ بِسَبْعٍ وَعِشْرِينَ دَرَجَةً "
It was narrated from Ibn 'Umar that the Messenger of Allah (ﷺ) said:
"Praying in congregation is twenty-seven times better than praying alone."
Reference: Sunan an-Nasa'i 837
In-book : Book 10, Hadith 61
English translation : Vol. 1, Book 10, Hadith 838