General Electric has a lot that's wrong with it, and the stock is not worth $20 per share — around the level where it opened on Monday, CNBC's Jim Cramer said.

Shares of GE were off sharply — and even went below $20 per share in early trading — after the conglomerate said before the market opened that it would cut its quarterly dividend in half to help free up capital to fund a turnaround. GE also announced an aggressive corporate restructuring.

Cramer — whose charitable trust owns the stock — said, "GE is one of the biggest mistakes of my career." Last month, when speculation about the dividend cut and some sort of restructuring were circulating, Cramer had said, "Rarely have I felt this stupid," while questioning what investors should do with the stock.

"I don't want to talk against my [investment], but I don't know how it's possible anyone thinks it should be worth $20," Cramer on Monday. "There's just a lot that's wrong." It should be "a 17 times earnings" stock, he added. GE said it now sees adjusted earnings for the year ahead of between $1 per share and $1.07 per share.

Cramer also calls GE's forecast of free cash flow between $6 billion and $7 billion "suspect," adding some analysts were skeptical. If new Chairman and CEO John Flannery "is approaching this pretty vigorously, why not just lower it [even further] if that's the case?" he asked.

There are divisions in the company that are not "up to snuff," said Cramer. But he added Flannery is a "no-nonsense guy" who has acknowledged GE's problems.

"Even though there is a lot that's not great here, Flannery is going to make it look like a regular company," Cramer said. "You're going to be able to look at it and say maybe it's not where Honeywell is but it can get there," he said, referring the very different story at industrial rival Honeywell, which has seen its stock surge 25 percent this year compared to GE's 37 percent decline since in 2017.