This is a linked open data (LOD) about date and time. "28 جمادى الأولى 1446" is a date of Hijri Calendar-TEST (Calendar ID: 103.1).
http://datetime.hutime.org/calendar/103.1/date/28_جمادى الأولى_1446
hcal:103.1/date/2460643.5
hcal:103.1/date/28_جمادى الأولى_1446
hcaldate:2460643.5
hcaldate:28_جمادى الأولى_1446