About 29.77 km/sec. Or 107,172 km/hr. The distance of the orbit is 939,336,203.4 km and stays pretty much the same--but should change slowly over hundreds of millions of years and get slightly smaller. The orbit is eliptical and the speed varies, going faster when we are closest to the sun around January and slowest in July, but the difference is small, varying from 30.29 km/sec at top speed down to 29.29 km/sec at the slowest.
making a small donation to science.ca.