10^x=0.3389
$$\\10^x=0.3389\\ log \;10^x=log\;0.3389\\ x=log\;0.3389\\$$
$${log}_{10}\left({\mathtt{0.338\: \!9}}\right) = -{\mathtt{0.469\: \!928\: \!431\: \!162\: \!621\: \!8}}$$