IEEE journal or conference total number of publications?
This addresses your journal of interest, specifically.

More generally, academic.research.microsoft.com can be used to find such information for other journals, as well as conferences.

Disclaimer: As user ff524 has pointed out in the comments of this answer, Microsoft Academic Search has stopped indexing/tracking "even a fraction of papers published since 2011", as reported by this article. I thank ff524 for pointing this out.