Euler Constant
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U+2107 is the Unicode hex value of the character Euler Constant, which is categorized as "uppercase letter" in the Unicode 6.0 character table.

"Euler Constant" was previously named "EULERS" in older versions of Unicode. In addition, U+2107 is a composite character comprising of one or more other Unicode characters modified or combined.

Unicode Character Information
Unicode Hex U+2107
General Category Uppercase Letter [Code: Lu]
Canonical Combining Class 0
Bidirectional Category L
Decomposition Mapping <compat> 0190
Mirrored N
Unicode Character Encodings
Euler Constant HTML Entity &#8455; (decimal entity), &#x2107; (hex entity)
Windows Key Code Alt 8455 or Alt +21071
Programming Source Code Encodings Python hex: u"\u2107", Hex for C++ and Java: "\u2107"
UTF-8 Hexadecimal Encoding 0xE28487
1 To type a Unicode symbol in Windows, hold down the ALT key and enter the decimal or hexadecimal code provided using the numeric keypad. The decimal alt code (Alt 8455) will only work on computers with support for this Unicode character in the active code page. The hexadecimal alt code (Alt +2107) will work for all Unicode characters provided Hex input from the numeric keypad is enabled.
* If the Euler Constant character does not display correctly in your browser, you may not have a Unicode font on your system that supports this particular symbol.