Narrated `Abdullah bin `Umar:
The Prophet (ﷺ) said, "The keys of the Unseen are five." And then he recited: 'Verily, the knowledge of the Hour is with Allah (alone).' (31.34) (ES)
USC-MSA web (English) reference: Vol. 6, Book 60, Hadith 301 (ES)
Arabic reference (ES): Book 65, Hadith 4778 (ES)