<Table> 24 Hour Fitness <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th> Type </Th> <Td> Private </Td> </Tr> <Tr> <Th> Genre </Th> <Td> Fitness </Td> </Tr> <Tr> <Th> Founded </Th> <Td> </Td> </Tr> <Tr> <Th> Founder </Th> <Td> Mark S. Mastrov </Td> </Tr> <Tr> <Th> Headquarters </Th> <Td> San Ramon, California, United States </Td> </Tr> <Tr> <Th> Number of locations </Th> <Td> 400 + </Td> </Tr> <Tr> <Th> Area served </Th> <Td> 17 U.S. states </Td> </Tr> <Tr> <Th> Key people </Th> <Td> Chris Roussos, CEO </Td> </Tr> <Tr> <Th> Owner </Th> <Td> AEA Investors, Ontario Teachers' Pension Plan </Td> </Tr> <Tr> <Th> Number of employees </Th> <Td> 22,000 + </Td> </Tr> <Tr> <Th> Website </Th> <Td> 24hourfitness.com </Td> </Tr> </Table> <Tr> <Th> Type </Th> <Td> Private </Td> </Tr> <Tr> <Th> Genre </Th> <Td> Fitness </Td> </Tr> <Tr> <Th> Founded </Th> <Td> </Td> </Tr>

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