DemographicsGeham is approximately 47.44 square kilometres. In 2016 the population of Geham was 489. The population is 55% male and 45% female. On average the monthly mortgage repayments in Geham are $1800 to $2399. The most common weekly income bracket is $300 to $399 per week. Weekly rents in the area are on average $0 to $74.