Well, the Hijri date 21 Rabi Al Thani 1177 corresponds to the Gregorian date Friday, 28 October 1763. This date lies in the fourth month of the Hijri year 1177 AH, which is Rabi Al-Thani of 1177 AH. Both this Hijri and Gregorian date occur on the single day that is Friday without any doubt. The Arabic date 1177/04/21 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 28 October 1763 to its equivalent Arabic date.
The following is the conversion of the Arabic date 21 Rabi Al Thani 1177 AH to its equivalent Gregorian date.
أَلَمْ تَرَ أَنَّ ٱللَّهَ أَنزَلَ مِنَ ٱلسَّمَآءِ مَآءًۭ فَسَلَكَهُۥ يَنَٰبِيعَ فِى ٱلْأَرْضِ ثُمَّ يُخْرِجُ بِهِۦ زَرْعًۭا مُّخْتَلِفًا أَلْوَٰنُهُۥ ثُمَّ يَهِيجُ فَتَرَىٰهُ مُصْفَرًّۭا ثُمَّ يَجْعَلُهُۥ حُطَٰمًا ۚ إِنَّ فِى ذَٰلِكَ لَذِكْرَىٰ لِأُو۟لِى ٱلْأَلْبَٰبِ
Hast thou not seen how Allah hath sent down water from the sky and hath caused it to penetrate the earth as watersprings, and afterward thereby produceth crops of divers hues; and afterward they wither and thou seest them turn yellow; then He maketh them chaff. Lo! herein verily is a reminder for men of understanding.
Surah Az-Zumar(39:21)