Well, the Hijri date 13 Rajab 1404 corresponds to the Gregorian date Saturday, 14 April 1984. This date lies in the seventh month of the Hijri year 1404 AH, which is Rajab of 1404 AH. Both this Hijri and Gregorian date occur on the single day that is Saturday without any doubt. The Arabic date 1404/07/13 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 14 April 1984 to its equivalent Arabic date.
The following is the conversion of the Arabic date 13 Rajab 1404 AH to its equivalent Gregorian date.
أَمْ عِندَهُمْ خَزَآئِنُ رَبِّكَ أَمْ هُمُ ٱلْمُصَۣيْطِرُونَ
Or do they own the treasures of thy Lord? Or have they been given charge (thereof)?
Surah At-Tur(52:37)