As the manager of a company you wish to invest in a new machine, which costs $4$ million. The annual interest rate is $6\%.$ The expected increase in revenue from the new machine in $2025$ and $2026$ is $1,400,000$ and $1,600,000,$ respectively. The expected increase in revenue in $2027$ is highly uncertain.

How much must the increase in revenue in $2027$ be at least to break even, given the data above?