By using the digits $0, 1, 2, 3, 4$ and $5$ (repetitions not allowed) any number of digits being used, the number of non-zero numbers that can be formed is

Number of numbers = Number of 1 digit number

-Numbers of 2 digit numbers$+....+$ Number of 6 digit numbers 

$\begin{array}{l}=5+5\times 5+5\times 5\times 4+5\times 5\times 4\times 3+5\times 5\times 4\times 3\times 2\\ +5\times 5\times 4\times 3\times 2\times 1\\ =5+25+100+300+600+600=1630\end{array}$