In East Asian tradition, each of the twelve zodiac animals has numbers it is said to get along with. These pairings grew out of the animal's temperament, the five elements, and folk numerology, and people still consult them for dates and number picks today. Here is what tradition says about the Horse.
Folk numerology holds that certain numbers resonate with each sign's character. The temperament attributed to the Horse, combined with the flow of the five elements, settled over centuries into the pairings passed down today.
Zodiac lucky numbers are folk tradition shared for entertainment — they don't guarantee any outcome.