Is he a Prophet?
Allah the Almighty declared:
" Remember Ishmael and Idris and Dhul Kifl, all were from among those who observe patience." (Ch 21:85-86)
Immediately following Job's story in the Qur'an, Almighty Allah also directed:
"Remember Our slaves, Abraham, Isaac, and Jacob (all) owners of strength (in worshipping Us) and also of religious understanding. Verily, We did choose them by granting them (a good thing ) the remembrance of the home (in the Hereafter and they used to make the people remember it and also they used to invite the people to obey Allah and to do good deeds for the Hereafter). And they are in Our Sight, verily of the chosen and the best! Remember Ishmael, Elisha, and Dhul Kifl all are among the best." (Ch 38:45-48)
It is obvious from his being mentioned and praised in the Glorious Quran along with those other prophets that Dhul - Kifl was also a prophet.
However, some of the Quranic commentators assumed that he was not a prophet but that he was righteous and strictly just.
The meaning of Dhul Kifl
Ibn Jarir narrated that he was not a prophet but he was a righteous man. He supported his people to suffice their needs and administered justice among them. That is why he was called Dhul - Kifl. (Dhul - Kifl literally means "possessor of, or giving, a double requital or portion".)