NEW YORK (AP) — Stocks that moved substantially or traded heavily Monday on the New York Stock Exchange and Nasdaq Stock Market:

NYSE

Best Buy Co. Inc., down $2.11 at $18.16

The electronics chain named Hubert Joly, the head of hospitality company Carlson and a turnaround expert, as its new CEO.

Aetna Inc., up $2.14 at $40.18

The health insurer said it will buy rival Coventry Health Care Inc. for $5.7 billion in order to bolster its Medicaid enrollment.

Lowe's Cos. Inc., down $1.61 at $26.26

The home improvement retailer said that its second-quarter net income fell 10 percent. Its results missed Wall Street expectations.

Nasdaq

Apple Inc., up $17.04 at $665.15

The iPhone maker became the world's most valuable company ever after its rising stock pushed the company's value to $624 billion.

ZAGG Inc., down $1.12 at $7.30

Robert Pedersen, the chairman and CEO of the cellphone and tablet accessory maker, left the company without providing a reason.

PhotoMedex Inc., up 67 cents at $11.60

The skin-care products maker said that its board of directors approved the repurchase of up to $25 million in company stock.

Bebe Stores Inc., down 59 cents at $5.68

The women's clothing retailer said that the company's president, Emilia Fabricant, resigned from the company for personal reasons.

Hibbett Sports Inc., down $2.95 at $56.27

A Raymond James analyst downgraded the sporting goods retailer to "Market Perform" from "Outperform" citing its high stock price.