Surah al Kafirun (109)

The Prophet said, ‘Recite surah al Kafirun and
then go to sleep after coming to its end, for it is a
clearance from shirk’
[Abu Dawud 4396 & Hakim 1/565]
Abdullah Ibn ‘Abbas and Anas Ibn Malik
(radiAllahu anhum) reported that the messenger
of Allah (salAllahu alayhi wasalam) said ‘It is
equivalent to a quarter of the Qur’an’
[at-Tirmidhi, 2818/A].
Abdullah ibn Umar Al-Khattab (radiAllahu anhu)
reported that Allah’s messenger (salAllahu alayhi
wasalam) said, “Qul Huw Allahu Ahad” is equal to
a third of the Qur’an and “Qul ya ayyuhal Kafirun”
is equal to a fourth of the Qur’an.”
[at-Tabarani, classed as Sahih]