(Yoosuf) 12 : 91
قَالُوا تَاللَّهِ لَقَدْ آثَرَكَ اللَّهُ عَلَيْنَا وَإِنْ كُنَّا لَخَاطِئِينَ
They said: "By Allah, surely Allah has given you heritage upon us, and indeed we have been the offenders".
The brothers accepted that Yoosuf got the Prophethood just like their father Yaqoob and his forefathers Ishaaq and Ibrahim. See explanation 2: 132-133 and 3: 102.