AMTD Digital stock has soared as much as 15,060% since its mid-July IPO on no apparent news, suggesting that the rally is being driven by the low-float nature of its outstanding shares and overwhelming demand for the stock. The Hong Kong-based tech firm trades on the New York Stock Exchange and priced its IPO at $7.80 per share, helping it raise $125 million in proceeds. On Tuesday, the stock hit a high of $1,182.50 on volume of just over 100,000 shares, briefly valuing the company at more than $150 billion. In a statement on Monday, AMTD Digital thanked its investors…