Earlier quoted context omitted.
I'd very much like to revive my old code (which I still have) at some point and see how well it runs on modern computers. My guess is that a typical 64-bit ~3 GHz quad-core machine could accomplish the same task in a few minutes today.
Hate to be the choosing beggar, and I appreciate all the answers, but ... everyone is answering about how long that 70 digit job would take now, when what I meant was, how big a number could you factor “overnight” with similar cost hardware.
The purpose of the FaaS (Factoring as a Service) project is to demonstrate that 512-bit integers can be factored in only a few hours, for less than $100 of compute time in a public cloud environment.
512b = 155 decimal digits.