I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?

Who Am I Math Puzzle

DAVID

Talking in roman numerals,
D = 500
At the center is 5 = V
The first number is I
The first letter of the alphabet is A

Thus they combine to form DAVID.