Surah Al-Isra, ayah 88

17:88

قُل لَّئِنِ ٱجۡتَمَعَتِ ٱلۡإِنسُ وَٱلۡجِنُّ عَلَىٰٓ أَن يَأۡتُواْ بِمِثۡلِ هَٰذَا ٱلۡقُرۡءَانِ لَا يَأۡتُونَ بِمِثۡلِهِۦ وَلَوۡ كَانَ بَعۡضُهُمۡ لِبَعۡضٖ ظَهِيرٗا ٨٨

Qul la inijtama'atil-insu wal-jinnu 'alā an ya'tū bimithli hādhal-qur'āni lā ya'tūna bimithlihī walaw kāna ba'duhum liba'din zahīrā

Say, "If mankind and the jinn gathered in order to produce the like of this Qur’ān, they could not produce the like of it, even if they were to each other assistants."