Odlum was first married, in 1915, to Hortense McQuarrie, first female department store head (at Bonwit Teller); they were divorced in 1935. His second wife, whom he married in 1936, was aviator Jackie Cochran. Odlum and Cochran were close friends of Amelia Earhart and her husband George P. Putnam, and the Odlums were financial backers of Earhart’s flying activities. They developed the Cochran-Odlum (C-O) Ranch in Indio, California where they lived after the 1950s.

After struggling as a corporate attorney in Salt Lake City, Odlum received an offer of a job at a New York firm, and in 1921 became vice-president of his primary client, Electric Bond and Share Company. In 1923, Odlum, a friend, and their wives pooled a total of $39,600 and formed the United States Company to speculate in purchases of utilities and general securities. Within two years, the company’s net assets had increased 17 fold to nearly $700,000. In 1928, Odlum incorporated Atlas Utilities Company to take over the common stock of his other company.

In 1948, Odlum sold RKO to Howard Hughes. Odlum was an investor in the 1954 production of the Broadway show The Pajama Game—during which actress Shirley MacLaine was discovered by Paramount Pictures producer Hal Wallis—and convinced Goldman Sachs’s head Sidney Weinberg to invest as well.

Odlum died in 1976 at the age of 84. His wife Jackie Cochran died four years later on August 9, 1980.

Odlum along with a business associate L.Boyd Hatch also purchased and developed Hatch’s Camp, also known as St. Ann’s Retreat, or Pine Glenn Cove, a mountainous retreat in Logan Canyon, Utah. In 2006, Pine Glenn Cove was placed on the National Register of Historic Places.