PROPHET MUHAMMAD (ﷺ) said:
Indeed there is a Surah in the Qur'an of thirty Ayat, which intercedes for a man until he is forgiven. It is [Surah] Tabarak Alladhi Biyadihil-Mulk (Surat Al Mulk).

Narrated: Jabir
The Prophet (ﷺ) would not sleep until he recited
1) Alif Lam Mim Tanzil (Surat As Sajdah)
2) Tabarak Alladhi Biyadihil-Mulk (Surat Al Mulk).