MDCCLXXVI is the Roman numeral representation for the number 1776. In this numeral, "M" stands for 1000, "D" for 500, "C" for 100, "L" for 50, "X" for 10, "V" for 5, and "I" for 1. Therefore, when combined, they add up to 1776, a significant year in history, particularly for the United States due to the Declaration of Independence.