Musnad Ahmad 27:352

Waki’ narrated to us, Abu Yahya al-Tawil narrated to me, from Abu Yahya al-Qattat, from Mujahid, from Ibn Umar, from the Prophet (peace be upon him), who said: "The people of the Fire will be made huge in the Fire, until the distance between the earlobe of one of them and his shoulder is a journey of seven hundred years. And the thickness of his skin is seventy cubits, and his molar is like Uhud."