In this study, it was investigated how domain-specific (number sense) and domain-general (working memory, creativity) factors explain the variance in mathematical abilities in primary school children. A total of 166 children aged 8 to 10 years old participated. Several tests to measure math ability, mathematical creativity, number sense, verbal and visual spatial working memory and creativity were administered. Data were analyzed with a series of correlation and regression analyses. Number sense, working memory and creativity were all found to be important predictors of academic and creative mathematical ability. Furthermore, groups with math learning disabilities (MLD) and mathematical giftedness (MG) were compared to a typically developing (TD) group. The results show that the MLD group scored lower on number line estimation and visual spatial working memory than the TD group, while the MG group differed from the TD group on visual spatial working memory and creativity. It is concluded that creativity plays a significant role in mathematics, above working memory and number sense.