[wurzddyx] Hubble constant in attohertz

If we take H0 to be 68 kilometer/second/megaparsec, then in metric units, it is 2.2 attohertz.

Inverse is 450 petasecond or 14 gigayear.  Is it just a coincidence that that's approximately the age of the universe?

It's not a coincidence that 14 billion light years is approximately the farthest can see.  Objects farther than that are receding from us faster than the speed of light, so we do not see light from them.  (There likely are objects farther than we can see: the universe is probably infinite in physical extent.)  Expressing the inverse Hubble constant in years is fun for describing the size of the observable universe in light years, but the original units are probably more practically useful when working out distances from redshifts.