The category of Number is often considered as rather simple comparing to such categories as case or nominal classification. However, a serious analysis of the morphosyntactic characteristics of the category shows that Number is an interesting and diverse category. The Niger-Congo languages demonstrate a great variety in the morphosyntactic characteristics of Number. At the first glance, the number in many languages refers to two types: a uniform marking of the number only in the plural (Mande - similar to English), the distinction of the singular by gender / class (Bantu - similar to Russian). However, the number in Mande and Bantu is fundamentally different from the number in English and Russian and refers to another typological category. Two more typological varieties in expression of number are demonstrated in the article: a special plural form for the names of people and pets (nyong, Adamawa), a kind of “split” under the influence of animacy hierarchy, and marking of number only in adjectives in attributive and predicative constructions without marking a number on a noun (Maya).