Well, the Hijri date 21 Dhul Qidah 1499 corresponds to the Gregorian date Monday, 19 October 2076. This date lies in the eleventh month of the Hijri year 1499 AH, which is Dhu Al-Qidah of 1499 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1499/11/21 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 19 October 2076 to its equivalent Arabic date.
The following is the conversion of the Arabic date 21 Dhul Qidah 1499 AH to its equivalent Gregorian date.
فَجُمِعَ ٱلسَّحَرَةُ لِمِيقَٰتِ يَوْمٍۢ مَّعْلُومٍۢ
So the wizards were gathered together at a set time on a day appointed.
Surah Ash-Shu'araa(26:38)