Is the account number field a string, or an number? (No quotes on numeric fields.) Also, double-check your date field to see if it's a date or date/time field. Date fields will have numbers between 1 and 36525, and date/time fields will have much larger numbers, provided the document you're looking for isn't before 11am on January 1st 1970.
Finally, I think the between operator needs parenths...
BETWEEN (1487930400 AND 1487934900)
-JD.