You can calculate the number of weeks by dividing the number of days by the number of days in a week. There are 7 days in a week, so:
$1,000,000 \text{ days} \times \frac{1 \text{ week}}{7 \text{ days}} = 142,857.14 \text{ weeks}$
Round up to the nearest hundredth to get 14,285.71 weeks.