Teak is about the same hardness as Honduran mahogany, which is to say medium density. Good strength-to-weight. It sands easily but can be difficult to cut (and hard on tools) because teak grows in silicaceous soils and takes vitreous silica up into the wood. Throws off sparks, too.

But the wood itself is of modest hardness compared to, say, jatoba or locust. There is a substantial hardness difference between annular earlywood and latewood, which causes a 'corduroy' effect similar to gymnosperms like douglas fir. So it's famously non-skid.
Teak is prone to grain checking and suffers rollover failure along crisp edges, but it generally doesn't exhibit running splinters like oak, cypress, or phillipine mahogany (
shorea spp.).
Along with oils, which are common in tropical species, teak contains waxy nodules in its grain called tyloses; these help with water resistance and are found in many rot-resistant woods like mahog, white oak, and black locust. More info that you really wanted, eh?
