DemographicsMount Prospect is approximately 13.95 square kilometres. In 2016 the population of Mount Prospect was 41. The population is 62% male and 38% female. On average the monthly mortgage repayments in Mount Prospect are $1400 to $1799. The most common weekly income bracket is $500 to $649 per week. Weekly rents in the area are on average $0 to $74.