The word(s) "believer" appears 651 time(s) in 556 verse(s) in Quran in Mohsin Khan translation.

(341) And who does more wrong than he who invents a lie against Allah or denies the truth (Muhammad صلى الله عليه وسلم and his doctrine of Islamic Monotheism and this Qur'an), when it comes to him? Is there not a dwelling in Hell for disbelievers (in the Oneness of Allah and in His Messenger Muhammad صلى الله عليه وسلم)?

(342) Within three to nine years. The decision of the matter, before and after (these events) is only with Allah, (before the defeat of the Romans by the Persians, and after the defeat of the Persians by the Romans). And on that Day, the believers (i.e. Muslims) will rejoice (at the victory given by Allah to the Romans against the Persians) -

(343) And on the Day when the Hour will be established, the Mujrimun (disbelievers, sinners, criminals, polytheists) will be plunged into destruction with (deep regrets, sorrows, and) despair.

(344) And on the Day when the Hour will be established - that Day shall (all men) be separated (i.e. the believers will be separated from the disbelievers).

(345) So glorify Allah [above all that (evil) they associate with Him (O believers)] when you come up to the evening [i.e. offer the (Maghrib ) sunset and ('Isha') night prayers], and when you enter the morning [i.e. offer the (Fajr) morning prayer].

(346) (And remain always) turning in repentance to Him (only), and be afraid and dutiful to Him; and perform As-Salat (Iqamat-as-Salat) and be not of Al-Mushrikun (the polytheists, idolaters, disbelievers in the Oneness of Allah).

(347) Say (O Muhammad صلى الله عليه وسلم): "Travel in the land and see what was the end of those before (you)! Most of them were Mushrikun (polytheists, idolaters, disbelievers in the Oneness of Allah)."

(348) That He may reward those who believe (in the Oneness of Allah - Islamic Monotheism), and do righteous good deeds, out of His Bounty. Verily, He likes not the disbelievers.

(349) And indeed We did send Messengers before you (O Muhammad صلى الله عليه وسلم) to their own peoples. They came to them with clear proofs, then, We took vengeance on those who committed crimes (disbelief, setting partners in worship with Allah, sins); and (as for) the believers, it was incumbent upon Us to help (them).

(350) And if We send a wind [which would spoil the green growth (tilth) brought up by the previous rain], and they see (their tilth) turn yellow - behold, they then (after their being glad,) would become unthankful (to their Lord Allah as) disbelievers. [Tafsir At-Tabari]