Twenty-Seven times more meritorious
Ibn `Umar (May Allah be pleased with them) reported: The Messenger of Allah (sallallaahu ’alayhi wa sallam) said, “Salat in congregation is twenty-seven times more meritorious than a Salat performed individually.”
[Al-Bukhari and Muslim].
Further Reading :
- The Excellence of Performing Salat (Prayers) in Congregation – Riyadh ul saaliheen