Help identify duplicate numbers and extract.

I have a large list of over 26,000 numbers, some are duplicates and I need to Identify them on a separate sheet. I don't want to simply "remove duplicates" as I need to identify which have duplicate entries. Please see the attached spreadsheet. I have highlightes some of the early dupes in grey. Thanks!!

Figured it out using conditional formatting to highlight all dupes and then used sort>sort by color to show only the highlighted duplicates.