



 
Pete, Do you want just a rough estimate or a very accurate one? First, if you have a number like 3.65 x 10^{69} you should see that there are 70 digits  it's the power of 10 that is important (why is it 70 and not 69?). Suppose you have 2^{84}. Since 2^{10} = 1024 ~ 1000 = 10^{3} then 2^{84} = 16 x 2^{80} ~16 x (10^{3})^{8} and that's 'about 16 x 10^{24} and it has about 26 digits. If you have 27^{48} however life is not so easy. You would need to use logarithms to handle your question in this case. If this is what you need, write back, Penny  


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences. 