Work management software provider Smartsheet is set to be acquired by Blackstone and Vista Equity Partners in an $8.4 billion deal.Investors of Smartsheet will receive $56.5 in cash per share, a 41% premium to the stock price.Smartsheet's platform is used by over 13 million professionals for project management and coordination.The acquisition allows Smartsheet to go private by February if there are no higher bids during the 45-day go-shop period.