The Candela to mega-candela equation converts a measurement of luminous intensity in candela (cd) to units of mega-candela (Mcd).
1`M"cd" = 10^6 * "cd"`
Candela (cd) - the SI unit of luminous intensity. "The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 1012 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian."1
Additional References:
Check out the Base Fundamental Units Conversion calculator for more light conversions.