410Mpc = 410 megaparsecs, which is about 1.3 billion light years

62M⊙ = 62 x the mass of the sun

The values have 90% error bars:

62+4−4M⊙ = 62 +/-4 solar masses

As the comments below say, the abstract says that three whole solar masses were converted to gravity waves when the black holes merged.

I'm not sure what the state of research into black hole mergers is, but the science that explains that number is going to be really interesting.