What IP address does heroku come from?

Question

MongoDB

I created an app and hosted it on heroku, where it was safely stolen! After an hour of sobbing and yelling, it turned out that the reason was the connection to the database. I use mongoDB Atlas, there is a "Network Access" item in the security settings, this is a list of IP addresses from which, and only which, you can connect to the database. What address should I specify in the case of heroku?

if it helps you, then here is the result of dns resolve of my application domain:

null [ '3.216.88.24', '23.22.144.165', '23.22.52.7', '3.219.96.23' ]

Answer 1

allow from any IP
to mine heroku Randomly takes the address

Answer 2

in general, as it turned out (thanks to Drno ), in Atlas you can add not only specific addresses, but entire ranges of addresses. 0.0.0.0/0 includes any address.