GitHub's REST API considers every pull request an issue, but not every issue is a pull request. For this reason, "Issues" endpoints may return both issues and pull requests in the response. You can identify pull requests by the pull_request key. Be aware that the id of a pull request returned from "Issues" endpoints will be an issue id. To find out the pull request id, use the "List pull requests" endpoint.
GitHub's REST API considers every pull request an issue, but not every issue is a pull request. For this reason, "Issues" endpoints may return both issues and pull requests in the response. You can identify pull requests by the pull_request key. Be aware that the id of a pull request returned from "Issues" endpoints will be an issue id. To find out the pull request id, use the "List pull requests" endpoint.