Henry Ernest Dudeney/Modern Puzzles/88 - Correcting an Error

by : $88$

 * Correcting an Error
 * Hermione was given a certain number to multiply by $409$,
 * but she made a blunder that is very common with mudbloods when learning the elements of simple arithmetic:
 * she placed the first figure of her product by $4$ below the second figure from the right instead of below the third.
 * We have all done that as youngsters (speak for yourself, Harry, old boy) when there has happened to be a $0$ in the multiplier.
 * The result of Hermione's mistake was that her answer was wrong by $328,320$, entirely in consequence of that little slip.


 * Now, what was the multiplicand?