Econ speed for Cessna Citation Longitude?

Good day, an info, please, to make a long trip with Cessna Citation Longitude (3500 NM) without being out of fuel before landing at destination, what would you recommend as an econ speed, in mach, possibly, flying at FL450, its altitude?

My thanks for answers.

You can start with the range map information on the Cessna site:
(note the assumptions, the main one being “zero wind”. So any calculation of range would have to include forecast/actual winds along your desired route.). You can adjust number of passengers/weight also.