Constant MAX_INPUTS_PER_BLOCK

const MAX_INPUTS_PER_BLOCK: usize = 24_386;

The maximum possible inputs you can have per block.

The smallest block (header + coinbase) you can have is 145B instead of 146B as stated in the stackexchange answer, but that doesn’t change the max possible input value.

https://bitcoin.stackexchange.com/questions/85752/maximum-number-of-inputs-per-transaction