The JavaScript Number type is implemented as an IEEE 754 double and as such any integer between -253 and 253 are represented without loss of precision. I can’t say I’ve ever missed explicitly declaring a value as an integer in JS. It’s dynamically typed anyways. There’s the languages people complain about and the ones nobody uses.
I hope you work in a field where worrying about your integers hitting larger values than 9 quadrillion is justified.