I am still skeptical for this . . the basic approximation formula gives a ballpark .. and when I put 159 million in the formula it gives me 12640500079500000 which is 12 quadrillion ... http://www.tools4noobs.com/online_tools/number_spell_words/
Reason I say this is - let's assume all 159 million bangs are expanded then 159*159 millions = 25 quadrillion
168668479408755201
Assuming your approximation "7 Quadrillion" means 7e15 (rather than 7e24 [1]), this is about 24 times as much.
[1] http://en.wikipedia.org/wiki/Quadrillion