Greek Capital Letter Phi
HTML Entity Browser Test:

U+03A6 is the Unicode hex value of the character Greek Capital Letter Phi, which is categorized as "uppercase letter" in the Unicode 6.0 character table.

Unicode Character Information
Unicode Hex U+03A6
General Category Uppercase Letter [Code: Lu]
Canonical Combining Class 0
Bidirectional Category L
Mirrored N
Lowercase Version U+03C6
Unicode Character Encodings
Greek Capital Letter Phi HTML Entity Φ (decimal entity), Φ (hex entity)
Windows Key Code Alt 0934 or Alt +03A61
Programming Source Code Encodings Python hex: u"\u03A6", Hex for C++ and Java: "\u03A6"
UTF-8 Hexadecimal Encoding 0xCEA6
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 0934) will only work on computers with support for this Unicode character in the active code page. The hexadecimal alt code (Alt +03A6) will work for all Unicode characters provided Hex input from the numeric keypad is enabled.
* If the Greek Capital Letter Phi character does not display correctly in your browser, you may not have a Unicode font on your system that supports this particular symbol.