Well, the Hijri date 20 Shawwal 1407 corresponds to the Gregorian date Tuesday, 16 June 1987. This date lies in the tenth month of the Hijri year 1407 AH, which is Shawwal of 1407 AH. Both this Hijri and Gregorian date occur on the single day that is Tuesday without any doubt. The Arabic date 1407/10/20 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 16 June 1987 to its equivalent Arabic date.
The following is the conversion of the Arabic date 20 Shawwal 1407 AH to its equivalent Gregorian date.
وَمِنْ حَيْثُ خَرَجْتَ فَوَلِّ وَجْهَكَ شَطْرَ ٱلْمَسْجِدِ ٱلْحَرَامِ ۚ وَحَيْثُ مَا كُنتُمْ فَوَلُّوا۟ وُجُوهَكُمْ شَطْرَهُۥ لِئَلَّا يَكُونَ لِلنَّاسِ عَلَيْكُمْ حُجَّةٌ إِلَّا ٱلَّذِينَ ظَلَمُوا۟ مِنْهُمْ فَلَا تَخْشَوْهُمْ وَٱخْشَوْنِى وَلِأُتِمَّ نِعْمَتِى عَلَيْكُمْ وَلَعَلَّكُمْ تَهْتَدُونَ
Whencesoever thou comest forth turn thy face toward the Inviolable Place of Worship; and wheresoever ye may be (O Muslims) turn your faces toward it (when ye pray) so that men may have no argument against you, save such of them as do injustice - Fear them not, but fear Me! - and so that I may complete My grace upon you, and that ye may be guided.
Surah Al-Baqara(2:150)
Sahih al-Bukhari
Virtues of Prayer at Masjid Makkah and Madinah
Chapter: The Masjid Quba (the Mosque of Quba)
Narrated Nafi`:
Ibn `Umar never offered the Duha prayer except on two occasions: (1) Whenever he reached Mecca; and he always used to reach Mecca in the forenoon. He would perform Tawaf round the Ka`ba and then offer two rak`at at the rear of Maqam Ibrahim. (2) Whenever he visited Quba, for he used to visit it every Saturday. When he entered the Mosque, he disliked to leave it without offering a prayer. Ibn `Umar narrated that Allah's Messenger (ﷺ) used to visit the Mosque of Quba (sometime) walking and (sometime) riding. And he (i.e. Ibn `Umar) used to say, "I do only what my companions used to do and I don't forbid anybody to pray at any time during the day or night except that one should not intend to pray at sunrise or sunset."
Sahih al-Bukhari 1191, 1192