Lambar Firayim lamba ce ta halitta mafi girma fiye da 1 wacce ba ta da masu rarrabuwar kawuna ban da 1 da kanta. Mafi ƙarancin lambar lamba biyu - mai raba hankalinsa ɗaya ne da biyu. Biyu kuma shine kawai ma firamin lamba. Duk sauran lambobin farko ba su da kyau, saboda duk sauran ma fiye da biyu sun kasu biyu. Lambobin farko na farko sune: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31…