Tatu

Tatu ni namba ambayo inafuata mbili na kutangulia nne. Kwa kawaida inaandikwa 3 lakini III kwa namba za Kiroma na ٣ kwa zile za Kiarabu.

3 ni namba tasa.

Marejeo
 Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London: Penguin Group (1987): 70–71

Viungo vya nje

 Tricyclopedic Book of Threes by Michael Eck
 Threes in Human Anatomy by Dr. John A. McNulty

 The Number 3 
 The Positive Integer 3
 Prime curiosities: 3

Jamii:Namba asilia