As character names:

U+3251 CIRCLED NUMBER TWENTY ONE character (㉑)

As raw characters:

㉑

As a string of HTML entities:

㉑

Decoder output:

Byte number 1 is decimal 227, hex 0xE3, octal \343, binary 11100011
This is the first byte of a 3 byte sequence.

Byte number 2 is decimal 137, hex 0x89, octal \211, binary 10001001
This is continuation byte 1, expecting 1 more.

Byte number 3 is decimal 145, hex 0x91, octal \221, binary 10010001
This is continuation byte 2, expecting 0 more.

U+3251	CIRCLED NUMBER TWENTY ONE
	# <circle> 0032 0031