https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104521/c-40bc/The C-40 B/C is based upon the commercial Boeing 737-700 business jet. The body of the C-40 is identical to that of the Boeing 737-700, but has winglets…The basic aircraft has auxiliary fuel tanks, a specialized interior with self-sustainment features and managed passenger communications.
I don’t know what 5000NM translates to in 737 time aloft, but I’d guess around 10 hours. Oooof.