There were 15,848 households out of which 27.7% had children under the age of 18 living with them, 24.8% were married couples living together, 23.2% had a female householder with no husband present, and 45.1% were non-families. 37.2% of all households were made up of individuals and 15.4% had someone living alone who was 65 years of age or older. The average household size was 2.46 and the average family size was 3.26.

How many households had children under the age of 18 living with them?