17 September 2021

• 260th day of the year. There were then 105 days left in 2021.
• 38th Friday of 2021.
• on the 37th week of 2021 (using ISO standard week number calculation).
• 89th day of Summer. There were 5 days left till Fall.
• Birthstone for this day: Sapphire

There are no major holidays or observances in the EU for this date.

• Constitution Day - United States
• Australian Citizenship Day - Australia
• Marathwada Liberation Day - India
• MIA Recognition Day - United States
• Día del Profesor - Argentina