Abu Hurairah (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) said, "Surat Ikhlas is equivalent to one-third of the Qur'an."[Muslim]. (RU)
App reference (RU): Book 9, Hadith 22 (RU)
Arabic/English book reference (RU): Book 9, Hadith 1012 (RU)