(CNN) Government investigators now believe that the data theft from the Office of Personnel Management computer systems compromised sensitive personal information, including Social Security numbers, of roughly 21.5 million people from both inside and outside the government, the government announced Thursday.

Of these, hackers obtained information from the security clearance applications -- known as SF-86's - of 19.7 million people.

Another 1.8 million were non-applicants comprised mostly of spouses and partners of applicants.

OPM had initially estimated the hackers obtained the files of 4 million people with information listed on the servers containing personnel data of current and former government employees.

Republicans called on President Barack Obama to remove OPM Director Katherine Archuleta

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