Well, the Hijri date 21 Rajab 1331 corresponds to the Gregorian date Wednesday, 25 June 1913. This date lies in the seventh month of the Hijri year 1331 AH, which is Rajab of 1331 AH. Both this Hijri and Gregorian date occur on the single day that is Wednesday without any doubt. The Arabic date 1331/07/21 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 25 June 1913 to its equivalent Arabic date.
The following is the conversion of the Arabic date 21 Rajab 1331 AH to its equivalent Gregorian date.
يَوْمَ يَبْعَثُهُمُ ٱللَّهُ جَمِيعًۭا فَيَحْلِفُونَ لَهُۥ كَمَا يَحْلِفُونَ لَكُمْ ۖ وَيَحْسَبُونَ أَنَّهُمْ عَلَىٰ شَىْءٍ ۚ أَلَآ إِنَّهُمْ هُمُ ٱلْكَٰذِبُونَ
On the day when Allah will raise them all together, then will they swear unto Him as they (now) swear unto you, and they will fancy that they have some standing. Lo! is it not they who are the liars?
Surah Al-Mujaadila(58:18)