You can express 5 million in Roman numerals in one of several ways. The most common way is with a V with two horizontal lines above it. Another way it is commonly expressed is as 5 Ms with single horizontal lines on top, or it can be written as ((V)).
The most common way to express 5 million in Roman numerals is as a V with two horizontal lines above it. This is because in Roman numerals, a single horizontal line above a number means that its value is multiplied by 1,000; two horizontal lines above a number means that its value is multiplied by 1,000,000 because 1,000 multiplied by 1,000 is 1,000,000. A similar calculation applies to a number with parentheses around it, as one set of parentheses around a number multiplies that number's value by 1,000, and two sets of parentheses multiplies the number's value by a million. Finally, a more straight-forward way of expressing the value could be as 5 Ms with single lines above them. An M is one thousand, and a single line above an M makes it a million. Five million can also be expressed as 10 Ds with single lines above them, since D equals 500.