You haven't provided any information about your output settings, such as resolution and frame rate, so it's hard to be specific.
But probably you've simply rendered to an uncompressed format - looks like an uncompressed AVI.
Send your render to Adobe Media Encoder, and render it as an H264 file at 1920x1080 resolution. Use a preset, this will reduce the chance of making errors. I'll bet the file size is then okay.
Here's the info:
Resolution: 1080 x 1920
Specific length: 6.021s
Cool, so just send your render to Adobe Media Encoder and use an H264 preset (such as "High Quality 1080p Full HD) to render a decent quality deliverable H264 file.
Of course, if you are using the file for something other than online delivery, you may need to consider other formats. But the uncompressed AVI you rendered previously will obviously be huge in almost all circumstances, and there are much more manageable options if you need lossless output.
Look at the AE help files for more guidance.