Answer:
Yes he is.
Though most adherents to Islam would say so it does, to a certain degree, depend on your definition of a prophet.
More enlightened members of other religious groups would accept that Mohammad was a very important prophet.
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Muslims are taught by Quran not to differentiate between God prophets and messengers. However, the five greatest prophet in Islam are Noah, Abraham, Moses, Jesus, and Muhammad (peace be upon them).
Quran says (English meaning translation): " The Prophet believes in what has been revealed to him by his Lord, and so do the faithful. Each one believes in God and His angels, His Books and the prophets, and We make no distinction between the apostles. For they say: "We hear and obey, and we seek Your forgiveness, O Lord, for to You we shall journey in the end." (Quran, chapter 2, verse 285)