Units shown on visuals

Well you technically could, but then I believe it will be then considered a string as Power BI does not natively support a apostrophe as a separator.
As per the format you described, I believe you wanted it formatted based on a scale of a million. I have wriiten a basic structure, but you will need to build upon it for cases where more than 100 million or cases where it is less than 100k but it will give you a head start:

Value with Apostrophe = SUBSTITUTE(
    FORMAT(SUM('Test Data'[Value]) / 1000000, "0.000"),
    ".",
    "'"
)

Here is the DAX to build the table to test it with:

Test Data = 
DATATABLE(
    "Category", STRING,
    "Value", INTEGER,
    "Description", STRING,
    {
        {"Sales", 1250000, "1.25 million"},
        {"Marketing", 750000, "750 thousand"},
        {"Operations", 2500000, "2.5 million"},
        {"HR", 125000, "125 thousand"},
        {"IT", 3750000, "3.75 million"},
        {"Finance", 500000, "500 thousand"},
        {"Research", 1875000, "1.875 million"},
        {"Support", 625000, "625 thousand"},
        {"Development", 4200000, "4.2 million"},
        {"Training", 300000, "300 thousand"}
    }
)

Personally, I would recommend avoiding this but if you really need it, I hope this helps!