لَا حَوْلَ وَلَا قُوَّةَ إِلَّا بِاللَّهِ
Transliteration
La hawla wa la quwwata illa billah
English meaning
There is no might nor power except with Allah.
When is it recited?
Recited frequently, especially in times of difficulty.
Its virtue
It is a treasure from the treasures of Paradise.
Source
Bukhari, Da'awat 50, 6384; Muslim, Dhikr 44, 2704