Furled is a free to use program which allows you to sanitize the file irregular files names from the downloaded files, for example when you save a webpage its gets saved on your computer with a irregular file name like the one shown below.
This application will add an option sanitize name in the right click context menu, just click on any improper file name and then select the option Sanitize filename
It will automatically rename the file with a nice proper name removing all the symbols and number from its name. If the file is not renamed due to any reason by after selecting this option in right click, it will retain the old and nothing will happen.
Here is how the above file name will look like after renaming.