There are many countries that use pennies as their minor currency unit and these are of different size. Since you have not bothered to specify which country's currency you intended, it is not possible to give a more useful answer.
15 centimeters
6 cm tall
7.5 cm
The average stack of 5 pennies is 7 mm tall.
Six pennies (copper coated steel) equal 0,972 cm.
200 cm
15 centimeters
The answer is 1,500 centimeters
A stack of 10 pennies (US or Canadian) is 1.5 centimeters.
6 cm tall
150 centimeters.
7.5 cm
A stack of 100 pennies is approximately 2.5 centimeters tall. Since a single penny is about 1.9 millimeters thick, stacking 100 of them results in a height of roughly 190 millimeters, which converts to 19 centimeters. Therefore, a stack of 100 pennies is not 0 centimeters tall; it is actually 19 centimeters tall.
The thickness of the US 1¢ coin is 1.55 mm. 100 of them in a stack rise to a lofty 155 mm = 15.5 cm.
Six pennies (copper coated steel) equal 0,972 cm.
The average stack of 5 pennies is 7 mm tall.
The height of a stack of one million pennies would depend on the thickness of each penny. A typical US penny has a thickness of about 1.55 mm. Therefore, a stack of one million pennies would be approximately 1,550,000 mm tall, which is equivalent to 1,550 meters or 1.55 kilometers.