Greek Capital Letter Iota With Macron
HTML Entity Browser Test:

U+1FD9 is the Unicode hex value of the character Greek Capital Letter Iota With Macron, which is categorized as "uppercase letter" in the Unicode 6.0 character table.

In addition, U+1FD9 is a composite character comprising of one or more other Unicode characters modified or combined.

Unicode Character Information
Unicode Hex U+1FD9
General Category Uppercase Letter [Code: Lu]
Canonical Combining Class 0
Bidirectional Category L
Decomposition Mapping 0399 0304
Mirrored N
Lowercase Version U+1FD1
Unicode Character Encodings
Greek Capital Letter Iota With Macron HTML Entity Ῑ (decimal entity), Ῑ (hex entity)
Windows Key Code Alt 8153 or Alt +1FD91
Programming Source Code Encodings Python hex: u"\u1FD9", Hex for C++ and Java: "\u1FD9"
UTF-8 Hexadecimal Encoding 0xE1BF99
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 8153) will only work on computers with support for this Unicode character in the active code page. The hexadecimal alt code (Alt +1FD9) will work for all Unicode characters provided Hex input from the numeric keypad is enabled.
* If the Greek Capital Letter Iota With Macron character does not display correctly in your browser, you may not have a Unicode font on your system that supports this particular symbol.