If you want to be alone, the best time is between four and five a.m. on a Tuesday. All the night owls have gone to roost and all the morning folks (venomous creatures) are yet to stir. One can walk the long lengths of yellow lines on urban thoroughfares unmolested an unquestioned.
If you want to go unnoticed, the best time is between nine and ten a.m. on a Wednesday. Everyone you might wake has gone to their worthless sales of labor. Anyone you do wake can't care to care. The world that might give you credence has gone to ground and you're left with nothing but hard, hateful morning.