Denver, IA has a population of 1,814 and is the 11,595th largest city in the United States. The population density is 1,158 per sq mi which is 1932% higher than the Iowa average and 1178% higher than the national average. The median age in Denver is 39 which is approximately 3% higher than the Iowa average of 38. In Denver, 75% of the population over 15 years of age are married, 98% speak English and 0% speak Spanish. 84% of Denver residents were born in Iowa, 15% were born out of state, 0% were born outside of the United States and 1% were foreign born.