Could photons from a flashlight propel itself through outerspace?

Photons do have momentum.  That's P = hf/c; where h is Planck's Constant, f is the frequency, and c is c.  But here's the deal.

Each one has very very very...very little momentum.  One photon with 1E6 cps frequency has 1.9734E-31 kg.m/s momentum for example.  So even trillions 1E9 per second, if you had them all aligned in the same direction, would not add up to much force.  In fact that would be 1.97E-22 Newtons.  Not enough to move a feather, let alone a flashlight.

And more to the point, those photons streaming out of your flashlight are not going in the same direction.  They are spreading out over space as they move farther away from the torch.  So their combined force is not co-linear with the axis of the flashlight.  Which means much of the force from the change in momentum is not along the length of the flashlight.  And that further weakens the thrust one might get from all those photons.