Apple's stock has closed above $600 for the first time, the same day the company announced plans to reward its shareholders with a dividend and a share buyback program.

The stock increased $15.53, or 2.65 percent, to close Monday at $601.10. It rallied in the final minutes of trading to reach that threshold.

On Thursday, the stock reached $600.01 briefly before falling to a closing price of $585.56.

Apple is the world's most valuable company, with a market capitalization of nearly $555 billion. It topped $500 billion for the first time in late February, a market value peak where few companies have ventured.