Ask the person who gave you that info.
That type of writing looks like someone tried to save some seconds on writing the specs... Take one minute to clarify and save yourself hours of guessing.
20.0000 has no sense as a unit. No modern notation groups numbers in 4 digits, even if you remove one 0, 20.000 has no sense using the dot as a (1000) separator (as in international format), a 20,000-pixel width banner is too big.
If it is a decimal point, 20 px has no sense either. What is PW? Pixel width? What is PD pixel density? All this, really, really has no sense. What is FC?
Define your requirements.
Is it a web add? for facebook or google adds? Search the recommended dimensions in pixels.
Is it for a magazine? define the magazine dimensions.
Are this 3.333" x 2.166" inches?
3.333 x 300PPI = 1000px
2.166 x 300PPI = 650px