According to one Hadith, the Prophet (PBUH) mentions 124,000 (or its roundabouts) prophets before him:
It was narrated that Abu Dharr said: I said: O Messenger of Allah, how many Prophets were there? He said: “One hundred and twenty four thousand.” I said: O Messenger of Allah, how many of them were Messengers? He said: “Three hundred and thirteen, a good number.” I said: O Messenger of Allah, who was the first of them? He said: “Adam.” …
Narrated by Ibn Hibbaan, 361
However, since no mention of an ‘exact’ number of Prophets has been mentioned in the “Sahih Hadith” meaning those of the great Imams: Bukhari, or Muslim, or Tirmidhi, or Abu Dawood, or Ibn Maajah, the authenticity of the above-mentioned Hadith is considered da’eef.
However, the Glorious Quran mentions specific names of the Prophets:
“Verily, We have inspired you (O Muhammad SAW) as We inspired Nooh (Noah) and the Prophets after him; We (also) inspired Ibrahim (Abraham), Ismail (Ishmael), Ishaque (Isaac), Yaqoob (Jacob), and Al-Asbat (the twelve sons of Yaqoob (Jacob)), Iesa (Jesus), Ayub (Job), Yoonus (Jonah), Haroon (Aaron), and Sulaiman (Solomon), and to Dawood (David) We gave the Zaboor (Psalms).
And Messengers We have mentioned to you before, and Messengers We have not mentioned to you, - and to Moosa (Moses) Allah spoke directly”
The tafsir of Ibn Kathir has the following to say on these verses:
Ibn Katheer (may Allah have mercy on him) said:
These are the names of the Prophets whose names are mentioned in the Qur’an: Adam, Idrees, Nooh, Hood, Saalih, Ibraaheem, Loot, Ismaa‘eel, Ishaaq, Ya‘qoob, Yoosuf, Ayyoob, Shu‘ayb, Moosa, Haroon, Yoonus, Dawood, Sulaymaan, Ilyaas, al-Yasa‘, Zakariya, Yahya, and ‘Eesa (blessings and peace be upon them), as well as Dhu’l-Kifl according to many commentators, and their leader is Muhammad (blessings and peace of Allah be upon him).
The words “and Messengers We have not mentioned to you” mean: other people who are not mentioned in the Qur’an.
Tafseer Ibn Katheer, 2/469
However it is the belief of every single Muslim that Our Prophet (PBUH) was final messenger and prophet of Allah Almighty, the Seal of Prophethood, and the Sealed Nectar of humanity itself.
May Allah Almighty allow us to be on the true path Insha ‘Allah & summa Ameen.