Well, the Hijri date 16 Dhul Hijjah 1405 corresponds to the Gregorian date Sunday, 1 September 1985. This date lies in the twelfth month of the Hijri year 1405 AH, which is Dhu Al-Hijjah of 1405 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1405/12/16 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 1 September 1985 to its equivalent Arabic date.
The following is the conversion of the Arabic date 16 Dhul Hijjah 1405 AH to its equivalent Gregorian date.
ذَٰلِكَ بِأَنَّ ٱللَّهَ لَمْ يَكُ مُغَيِّرًۭا نِّعْمَةً أَنْعَمَهَا عَلَىٰ قَوْمٍ حَتَّىٰ يُغَيِّرُوا۟ مَا بِأَنفُسِهِمْ ۙ وَأَنَّ ٱللَّهَ سَمِيعٌ عَلِيمٌۭ
That is because Allah never changeth the grace He hath bestowed on any people until they first change that which is in their hearts, and (that is) because Allah is Hearer, Knower.
Surah Al-Anfaal(8:53)