As character names:

U+2209 NOT AN ELEMENT OF character (∉)

As raw characters:

∉

As a string of HTML entities:

∉

Decoder output:

Byte number 1 is decimal 226, hex 0xE2, octal \342, binary 11100010
This is the first byte of a 3 byte sequence.

Byte number 2 is decimal 136, hex 0x88, octal \210, binary 10001000
This is continuation byte 1, expecting 1 more.

Byte number 3 is decimal 137, hex 0x89, octal \211, binary 10001001
This is continuation byte 2, expecting 0 more.

U+2209	NOT AN ELEMENT OF
	: 2208 0338