The Script Small E symbol (ℯ). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Letterlike Symbols.
The quickest way is to copy ℯ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
ℯ is U+212F (decimal 8495).
Use ℯ in HTML to render ℯ on a web page.
On Windows you can type it with Alt+8495 (hold Alt and enter the number on the numeric keypad).
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