As character names:

U+FF03 FULLWIDTH NUMBER SIGN 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 188, hex 0xBC, octal \274, binary 10111100
This is continuation byte 2, expecting 1 more.

Byte number 4 is decimal 131, hex 0x83, octal \203, binary 10000011
This is continuation byte 3, expecting 0 more.

U+FF03	FULLWIDTH NUMBER SIGN
	# <wide> 0023