8400 is a pure number, with no units associated so it is impossible to answer the question in a sensible way. 0.84 m is very much smaller than 8400 kilometres but very much larger than 8400 nanometres!
< > = Greater than , less than and equal too
Is < Less than or Greater than or > Greater than or Less than
0.3 is greater than 0.08
Less than < Greater than >
Greater than: > Less than: <
greater than is > less than is <
less than
greater than > less than < pointy end towards the smaller value
Less
less
greater than= > less than= <