Cyrillic Capital Letter Double Monocular O
HTML Entity Browser Test:

U+A66C is the Unicode hex value of the character Cyrillic Capital Letter Double Monocular O, which is categorized as "uppercase letter" in the Unicode 6.0 character table.

Unicode Character Information
Unicode Hex U+A66C
Character Name CYRILLIC CAPITAL LETTER DOUBLE MONOCULAR O
General Category Uppercase Letter [Code: Lu]
Canonical Combining Class 0
Bidirectional Category L
Mirrored N
Lowercase Version U+A66D
Unicode Character Encodings
Cyrillic Capital Letter Double Monocular O HTML Entity Ꙭ (decimal entity), Ꙭ (hex entity)
Windows Key Code Alt 42604 or Alt +A66C1
Programming Source Code Encodings Python hex: u"\uA66C", Hex for C++ and Java: "\uA66C"
UTF-8 Hexadecimal Encoding 0xEA99AC
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 42604) will only work on computers with support for this Unicode character in the active code page. The hexadecimal alt code (Alt +A66C) will work for all Unicode characters provided Hex input from the numeric keypad is enabled.
* If the Cyrillic Capital Letter Double Monocular O character does not display correctly in your browser, you may not have a Unicode font on your system that supports this particular symbol.