Well, the Hijri date 20 Rajab 1189 corresponds to the Gregorian date Friday, 15 September 1775. This date lies in the seventh month of the Hijri year 1189 AH, which is Rajab of 1189 AH. Both this Hijri and Gregorian date occur on the single day that is Friday without any doubt. The Arabic date 1189/07/20 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 15 September 1775 to its equivalent Arabic date.
The following is the conversion of the Arabic date 20 Rajab 1189 AH to its equivalent Gregorian date.
فَقُلْنَا يَٰٓـَٔادَمُ إِنَّ هَٰذَا عَدُوٌّۭ لَّكَ وَلِزَوْجِكَ فَلَا يُخْرِجَنَّكُمَا مِنَ ٱلْجَنَّةِ فَتَشْقَىٰٓ
Therefor we said: O Adam! This is an enemy unto thee and unto thy wife, so let him not drive you both out of the Garden so that thou come to toil.
Surah Taa-Haa(20:117)