It is narrated from Hazrat Aisha (may Allah be pleased with her) that if a group of about one hundred Muslims offers the funeral prayer for a Muslim deceased and intercedes for him, their intercession is accepted for him.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 13804
Hadith Gradingحکم دارالسلام:إسناداه - أي إسناد عائشة و إسناد أنس - صحيحان، م: 947