Well, the Hijri date 13 Ramadan 1406 corresponds to the Gregorian date Wednesday, 21 May 1986. This date lies in the ninth month of the Hijri year 1406 AH, which is Ramadan of 1406 AH. Both this Hijri and Gregorian date occur on the single day that is Wednesday without any doubt. The Arabic date 1406/09/13 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 21 May 1986 to its equivalent Arabic date.
The following is the conversion of the Arabic date 13 Ramadan 1406 AH to its equivalent Gregorian date.
۞ وَسَارِعُوٓا۟ إِلَىٰ مَغْفِرَةٍۢ مِّن رَّبِّكُمْ وَجَنَّةٍ عَرْضُهَا ٱلسَّمَٰوَٰتُ وَٱلْأَرْضُ أُعِدَّتْ لِلْمُتَّقِينَ
And vie one with another for forgiveness from your Lord, and for a paradise as wide as are the heavens and the earth, prepared for those who ward off (evil);
Surah Aal-i-Imraan(3:133)