Even after the download finishes, you should verify the file yourself. Oracle provides checksums (MD5 or SHA) on the download page.
Here is the verified guide to downloading and installing Oracle SQL Developer, along with the solution for that specific error code. oracle sql developer download 2143 download verified
Designed for Red Hat, Oracle Linux, and other Linux distributions. Step 2: How to Verify Your Download (Checksum Verification) Even after the download finishes, you should verify