Today's conventional conversion of 11th September 2009 into Roman numerals is XI-September-MMIX whether or not the Romans themselves did it this way is questionable.
November 11th 2009 can also be written as 11-11-2009 which is written in Roman numerals as XI.XI.MMIX
The date November 11th 2009 can also be written as 11-11-2009 and in Roman numerals this can be written as XI.XI.MMIX
II-XI-MMIX
The date September 23rd 2009 can also be written as 09-23-2009 and this can be represented by the Roman numerals IX.XXIII.MMIX
November is the 11th month. The number 11 as a Roman numeral is XI and the number 2009 is MMIX.
November 11th 2009 can also be written as 11-11-2009 which is written in Roman numerals as XI.XI.MMIX
The date November 11th 2009 can also be written as 11-11-2009 and in Roman numerals this can be written as XI.XI.MMIX
II-XI-MMIX
The date September 23rd 2009 can also be written as 09-23-2009 and this can be represented by the Roman numerals IX.XXIII.MMIX
November is the 11th month. The number 11 as a Roman numeral is XI and the number 2009 is MMIX.
5-11-2009 or May 11th, 2009. Or 5 November 2009
IX/IV/MMIX
IX-II-MMIX
IX-XIX-MMIX
Today's conventional conversion of 20th September 2009 into Roman numerals is XX-September-MMIX.However, there is strong evidence to support the fact that the Romans themselves would have written the above date as XX-September-MMVIIII.
As you asked this question on 15th September 2009, which can also be written as 15-09-2009, this date in Roman numerals would be XV.IX.MMIX
If you write September 09 2009 as 09-09-2009 then you can write using these numerals IX (9) and MM = 2000, so 09-09-2009 becomes IX.IX.MMIX