If the planet's radius is 5378, then the distance around its equator is
(2π) x (5378) = 33,790.97 .
Any point on the equator takes 24 hours to go all the way around once, so its linear speed is
(33,790.97) / (24)
Speed = 1,407.96 units/hour
Speed = 23.466 units/minute
Speed = 0.391 unit/second
The 'unit' is the same as whatever unit the '5378' has.