39600 LEs and 532 I/O — sizing the fit
39600 logic elements and 532 I/O on a 780-FBGA. The EP4CE75F23C7N has 75408 LEs but only 292 I/O.
780-FBGA — routing and rework considerations
The 780-ball FBGA measures 29x29 mm.
Sourcing this part through independent distribution
For dual-source resilience, the MAX 10 family peers 10M40DCF672C7G and 10M40DAF672C8G offer similar logic density (40000 LEs) and I/O count (500) in a 672-ball package, but note the different architecture and tool flow (Quartus Prime with MAX 10 device support). They are not pin-compatible drop-ins, but a viable architectural alternate if you control the FPGA image and PCB layout.
