One or two AA or AAA batteries can power a 1980s pager for a whole year without recharging. This is because most pagers of that time period are one-way. Since it only listens, it avoids the energy cost of constantly transmitting to all towers in range. So it’s even better than a feature phone (dumb phone). The beneficial side-effect: you’re untrackable apart from being in the service area.

It’s not a good state of affairs in the US though. All but 2 pager service providers have gone out of business. It’s a duopoly and last time I checked you can only get annual contracts for a price that’s higher than prepaid mobile service. You also can no longer buy new pagers because no one makes them (apart from POCSAG hobbyist varieties which then require you to build your own transmitter). This means you’re limited to whatever still exists in the 2nd hand market for hardware.

So it sucks in the US. Is it better anywhere else? In principle pagers are still important for first responders because they’re more reliable than SMS, so they should really still exist everywhere at least to the extent that competence prevails.