Aleph = 1: the first letter and the first numeral. Ordinal 1, reduced 1, no final form. Spelled in full, its name אלף = 1+30+80 = 111.
Meaning
Aleph is the ox — the old pictogram is a horned head — and it is the alphabet's silent letter, the glottal catch that carries any vowel, which is why Sefer Yetzirah makes it the mother of air. Its 1 is the numeral of unity, so the alphabet begins with a letter that has no sound of its own and the value of oneness at once. The aggadah in which the letters petition to begin the Torah — and aleph, consoled with the first place among the letters and the first word of the Decalogue, is the tradition's own comment on that arrangement.