Simplify the following text for a Grade 7 native English-speaking person.
Original: The population density is 11,636.5 \/ km2 ( 30,239.2 \/ mi2 ) , fourth highest in the nation after neighboring communities of Guttenberg , Union City and West New York .
Simplified: The population density is 11,636.5 \/ kmÂ ( 30,239.2 \/ miÂ ) .