Mount Summit, IN has a population of 541 and is the 19,087th largest city in the United States. The population density is 2,863 per sq mi which is 1495% higher than the Indiana average and 3060% higher than the national average. The median age in Mount Summit is 42 which is approximately 13% higher than the Indiana average of 37. In Mount Summit, 53% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 86% of Mount Summit residents were born in Indiana, 14% were born out of state, 0% were born outside of the United States and 0% were foreign born.