Ramanujan was a genius, but he didn't just factor 1729 on the spot in the hospital bed. According to Wikipedia, he'd already known about it a few years before, so it was just coincidence that Hardy happened to present a number he already knew about, although to be honest, he probably knew interesting facts about most numbers below 1 million or so.
Whenever I need an arbitrary const int I use 1729. I've left a trail of 1729s in the codebases I've touched over the years, and I like the thought of other hackers recognising the number when they have to fix the bugs I've left behind.
Ramanujan was an extraordinary mathematician who was able to intuit (and then prove) many really surprising formulas. I have no idea how a movie is going to work since most of these results are far too heavy for a movie screen and without it how can you understand the man ?
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