Praying in congregation is twenty-seven degrees better than praying alone. [Sahih/Authentic] - [Al-Bukhari and Muslim
"«صلاةُ الجَمَاعَة أَفضَلُ من صَلاَة الفَذِّ بِسَبعٍ وعِشرِين دَرَجَة». [صحيح.] - [متفق عليه.]"