Answer
Praying in congregation (Jama'at) with its conditions is preferable to praying individually. Its preference is stronger in the dawn, sunset and night prayers. A noble hadith says: "A salat [in congregation] behind a learned scholar is like [praying] a thousand cycles; and behind a Qurayshi is like [praying] a hundred cycles." As the number of the worshippers increases, the preference [and the reward] also increases.