WASHINGTON (Reuters) - US President Barack Obama was worth millions of dollars in 2010, mostly due to royalties from the sale of his books, financial disclosure forms showed on Monday. Obama had between $100,001 and $1,000,000 from Audacity of Hope, a book tied in with his run for the White House in 2008, and between $1,000,001 and $5,000,000 from Dreams from My Father, a memoir about his upbringing, according to the forms. Both books were published before Obama became president. The records showed Obama and his wife, Michelle, had some retirement savings accounts with the mutual fund company Vanguard and checking accounts at J.P. Morgan Chase and Northern Trust. They also own Treasury bills and have college savings accounts for their daughters Malia and Sasha. In tax returns released in April, the Obamas reported an adjusted gross income of $1,728,000.