Presumably you mean what date will have the most Roman numerals in the 21st century?
If so then it will be December 31 2088 which will be:
XII-XXXI-MMLXXXVIII
actually, August 28, 2088 will be the most Roman Numerals in the 21st Century:
VIII-XXVIII-MMLXXXVIII
It is Good Friday and today's date is April 22 2011 which in Roman numerals is IV-XXII-MMXI
The date 03.04.1989 is written in roman numerals as III.IV.MCMLXXXIX
The date 17-04-2009 in Roman Numerals would be XVII.IV.MMIX
To date the longest year would have been MDCCCLXXXVIII(1888) compared with M for the year 1000 or MMIX for the current year 2009.
2017 is the equivalent of MMVII in Roman numerals
It is Good Friday and today's date is April 22 2011 which in Roman numerals is IV-XXII-MMXI
The date 03.04.1989 is written in roman numerals as III.IV.MCMLXXXIX
The date 17-04-2009 in Roman Numerals would be XVII.IV.MMIX
To date the longest year would have been MDCCCLXXXVIII(1888) compared with M for the year 1000 or MMIX for the current year 2009.
The date 06.12.1983 in Roman numerals would be VI.XII.MCMLXXXIII
2017 is the equivalent of MMVII in Roman numerals
The date 15-04-1990 can be represented by the Roman numerals XV.IV.MCMXC
The date 25-03-2006 in Roman numerals would be XXV.III.MMVI
The date 01-06-1981 in Roman numerals is I.VI.MCMLXXXI
The date of birth 19101989 in Roman numerals is XIX.X.MCMXCIX.
The date of birth 05041971 in Roman numerals is V.IV.MCMLXXI.
The date 19-02-1986 written in Roman numerals would be XIX.II.MCMLXXXVI