If your base bet is 1 satoshi you would need about 150.000.000 bets to get to 1.2 btc
I think that should usually depend on what kind of martingale strategy you are using.
Some people martingale at 50%. Some also matingale at 10% or at 90%.
They just increase their base bets by different ratios.
Also, at 90% a martingale of 7-8 would get you at >1 BTC.
I dont see how you can use 90% at 1 satoshi bet, that means you would win like what 0.1 satoshi each win?
And anyways it would be the same at any ratio