Get AWS SQS queue URL?

An AWS SQS queue URL looks like this:

http://ift.tt/1O9C30P

And here are the parts broken down:

Always same | Stored in env var | Always same   | ?          | Stored in env var
sqs         | us-east-1         | amazonaws.com | 1234567890 | default_development

So I can reconstruct the queue URL based on things I know except the 1234567890 part.

What is this number and is there a way, if I have my AWS creds in env vars, to get my hands on it without hard-coding another env var?