<Table> <Tr> <Th_colspan="2"> Seventh - day Adventist Church </Th> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th> Classification </Th> <Td> Protestant </Td> </Tr> <Tr> <Th> Orientation </Th> <Td> Adventist </Td> </Tr> <Tr> <Th> Polity </Th> <Td> Polity of the Seventh - day Adventist Church </Td> </Tr> <Tr> <Th> Region </Th> <Td> Worldwide </Td> </Tr> <Tr> <Th> Founder </Th> <Td> <Ul> <Li> Joseph Bates </Li> <Li> James White </Li> <Li> Ellen G. White </Li> <Li> J.N. Andrews </Li> </Ul> </Td> </Tr> <Tr> <Th> Origin </Th> <Td> May 21, 1863 Battle Creek, Michigan </Td> </Tr> <Tr> <Th> Separations </Th> <Td> <Ul> <Li> SDA Reform Movement (separated 1925, small minority) </Li> <Li> Shepherds Rod - Davidian SDAs (separated 1929, small minority) </Li> </Ul> </Td> </Tr> <Tr> <Th> Congregations </Th> <Td> 81,552 churches, 69,909 companies </Td> </Tr> <Tr> <Th> Members </Th> <Td> 20,008,779 </Td> </Tr> <Tr> <Th> Hospitals </Th> <Td> 175 </Td> </Tr> <Tr> <Th> Nursing homes </Th> <Td> 136 </Td> </Tr> <Tr> <Th> Aid organization </Th> <Td> Adventist Development and Relief Agency </Td> </Tr> <Tr> <Th> Primary schools </Th> <Td> 5,332 </Td> </Tr> <Tr> <Th> Secondary schools </Th> <Td> 2,296 </Td> </Tr> <Tr> <Th> Tertiary institutions </Th> <Td> 115 </Td> </Tr> <Tr> <Th> Other name (s) </Th> <Td> Adventist church, SDA (informal) </Td> </Tr> <Tr> <Th> Official website </Th> <Td> www.adventist.org </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Seventh - day Adventist Church </Th> </Tr>

How many members of the seventh day adventist