The most auspicious number is 4. "2" means "harmony" and "6" means "smoothness".
From the glyph shape of "四": a house full of children and grandchildren, a prosperous population
The Chinese character "四" means a small "son" surrounded by railings on all sides, protecting it like a treasure. Smooth and stable means that the square house is full of children and grandchildren and the population is prosperous. The first requirement for building a house is "four and eight stable", so "four" has been a lucky number for a house since ancient times.
The Arabic numeral "4" resembles a flag. It is the benchmark among all numbers. "0 is like an egg, 1 is like a pencil, 2 is like a duck, 3 is like an ear, 4 is like a flag, 5 is like a hook, 6 is like bean sprouts, 7 is like a sickle, 8 is like handcuffs, and 9 is like a tadpole."
Extended information:
"1". In traditional Chinese culture, 1, 2, 3, 4, and 5 correspond in turn to birth, old age, illness, death, and suffering (6 in turn represents life, and so on). The size of the door made by the carpenter, the number of words written on the central beams of the hall by the painter, etc. must comply with this rule.
"2". "2" means perfection, the balance of yin and yang, and the happiness of two.
"3". In ancient times, there were "three friends of Suihan" and "three soldiers of the three armies". Nowadays, the homophones are "sheng" and "shang". It is favored by many people.
"4". Like "2", "4" means perfection, the balance of yin and yang, talents in all directions, and the four seasons of the year. Unfortunately, some people say that it should not be homophonic with "death".