CotEditor can popover the information about the selected character. Select exactly a single character and select “Inspect Character” in “Text” menu or press Cmmand+Option+I keys.
In the popover, zoomed character, the Unicode character name, block name, general category, and the Unicode code point will be displayed. It shows also UTF-16 codes of each character in braces if the character is a surrogate pair. If the selected letter consists actually of multiple Unicode characters, only the code points and Unicode name will be listed-up.