Apple still represents a reasonable investment opportunity even as it's market value charges toward $1 trillion, according to Aswath Damodaran.

"I think it's reasonably valued. ... If you look at the amount of cash they have, and you take that out of the mix, they're actually not trading at that high a multiple of earnings,"

the professor of finance at New York University's Stern School of Business told CNBC's "Squawk Alley" on Wednesday. "So I think, unlike the other tech stocks, which are trading richly relative to future earnings, Apple is still a reasonably priced stock."

Apple shares rallied 5 percent Wednesday, a day after reporting strong fiscal third-quarter earnings. Apple hit the $200 per share mark during mid-morning trading and remains within a few percentage points of a $1 trillion market capitalization, a feat no other U.S. public company has ever achieved.

"This is a cash machine, but it's not going to be a high-growth company: those days are behind it," said Damodaran who is widely regarded as one of the foremost experts in valuing companies and is often referred to as Wall Street's "dean of valuation."

"It is the greatest cash machine in history and I'll say that again because it's a company — it can't stop throwing off cash. I mean companies wish they had Apple's problem," he added.

Apple said Tuesday it had $243.7 billion in cash on hand at the end of the third quarter. That cash hoard alone is bigger than the market value of 484 companies in the S&P 500, including Intel and AT&T.

The company trades at 14.9 times analysts' earnings estimates for the fiscal year 2019, compared with a forward P/E ratio of 15.9 for the S&P 500.

"I think as long as you're realistic that you're buying a low-growth company that's going to throw off cash like crazy for the next few years, then I think you're getting a reasonably good investment," Damodaran said.

At the latest reading, shares of Apple were up 33 percent over the past year and up 18.4 percent during the last three months.