Question 3299
To find factors of a number N it is enough to search the odd numbers from 3-{{{sqrt(N)}}}. The table below whether or not a number is a factor of 499 by checking whether or not 499/n has a remainder (you will need to scroll down to see the table).
<table>
<tr>
<th>n</th><th>remainder</th>
</tr>
<tr>
<td>3</td><td>yes</td>
</tr>
<tr>
<td>7</td><td>yes</td>
</tr>
<tr>
<td>13</td><td>yes</td>
</tr>
<tr>
<td>17</td><td>yes</td>
</tr>
<tr>
<td>19</td><td>yes</td>
</tr>
<tr>
<td>21</td><td>yes</td>
</tr>
</table>

Since 499 has no factors, it must be prime. I skipped some possible values like 5 and 9. Do you know why?