Amazon's Work Force Grew 77 Percent Over Last Year to Over 500,000

Staffing at online mega-retailer Amazon has ballooned 77 percent over the past year – to 541,900 full and part-time workers — making it America's second-largest publicly traded employer, USA Today reported.

The bump is due largely to its purchase in August of Whole Foods, and that of Souq.com, a Middle East-based e-commerce company, in July, as well as a rapid buildout of regional warehouses, the outlet reported.

The headcount does not include the more than 120,000 seasonal jobs it is expected to add for the holidays, the outlet noted.

Even without Whole Foods and Souq, Amazon's staffing is up 42 percent over last year, the company said in its earnings call Thursday, USA Today reported.

The headcount puts Amazon second only to Walmart, with 2.3 million workers, among publicly traded U.S. companies. Kroger, with 433,000 — and it comes as 238 cities nationwide vie to be selected as the company's second headquarters, where it will employ 50,000 people, USA Today reported.

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