As character names:
U+FDD9 <not a character> character ()
As raw characters:
As a string of HTML entities:

Decoder output:
Byte number 1 is decimal 240, hex 0xF0, octal \360, binary 11110000 This is the first byte of a 4 byte sequence. Byte number 2 is decimal 143, hex 0x8F, octal \217, binary 10001111 This is continuation byte 1, expecting 2 more. Byte number 3 is decimal 183, hex 0xB7, octal \267, binary 10110111 This is continuation byte 2, expecting 1 more. Byte number 4 is decimal 153, hex 0x99, octal \231, binary 10011001 This is continuation byte 3, expecting 0 more. U+FDD9 <not a character>