Well, the Hijri date 24 Dhul Hijjah 1421 corresponds to the Gregorian date Monday, 19 March 2001. This date lies in the twelfth month of the Hijri year 1421 AH, which is Dhu Al-Hijjah of 1421 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1421/12/24 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 March 2001 to its equivalent Arabic date.
The following is the conversion of the Arabic date 24 Dhul Hijjah 1421 AH to its equivalent Gregorian date.
فَكَذَّبُوهُ فَنَجَّيْنَٰهُ وَمَن مَّعَهُۥ فِى ٱلْفُلْكِ وَجَعَلْنَٰهُمْ خَلَٰٓئِفَ وَأَغْرَقْنَا ٱلَّذِينَ كَذَّبُوا۟ بِـَٔايَٰتِنَا ۖ فَٱنظُرْ كَيْفَ كَانَ عَٰقِبَةُ ٱلْمُنذَرِينَ
But they denied him, so We saved him and those with him in the ship, and made them viceroys (in the earth), while We drowned those who denied Our revelations. See then the nature of the consequence for those who had been warned.
Surah Yunus(10:73)