This is always a curveball because the problem is hidden away in the recesses of the operating system that we generally don't visit.
Whether your machine has 4 GB of memory or is attached to 512GB of virtual memory through a shared pool (this actually came up yesterday), there is a tunable per user parameter set on how much is available at any one time.
One tell is that 2^{5.8914} \approx 2^{16}. But no one I know goes around thinking in base2 all the time.
But all modern OSs that I know do.
It turns out that in the unices (can't say about windows) there is a command to manage this
$ 578: ulimit
unlimited
See man ulimit for guidance on how to adjust yours.