Like in Western culture, each number has their unique meaning in Chinese culture. Some are thought to be auspicious and some are inauspicious according to the pronunciation of the number and the similarity of it with another word.
The Most Auspicious Numbers: 6, 8, 9:
Six, eight and nine are regarded as the luckiest numbers in China. All of their homophones have auspicious meanings.
The number 6 pronounced as 'Liu' means smooth and well-off. In Chinese people’s eyes, it stands for everything will go smoothly. So when choosing telephone numbers, people like more number 6s in it. Eight has the similar pronunciation with 发 (means wealth and fortune in Chinese), so Chinese people favor it very much especially for businessmen. The number 9 pronounced as Jiu (久) in Chinese means everlasting, longevity and eternality. In Chinese culture, it is associated with the Emperor of China. You can see the Emperor's robes have nine dragons and the Beijing Forbidden City has totally 9,999 and a half rooms. For lovers, 99, 999, or 9999 roses are usually sent to present the eternal love.
The most Inauspicious Numbers: 4, 7
Four is regarded as the unluckiest number as the word for 死（death）sounds similar to four in Chinese. So when mention the number 4, the Chinese people usually associate it with death. It is disliked by the Chinese people like the western people don’t like the number 13. But it also has a good meaning as it has the same pronunciation with the word发 (fortune) in Chinese.
Another inauspicious number is seven which have the meaning of gone. It also has the same pronunciation with 欺 (cheat) in Chinese. So in daily life, Chinese people usually avoid to use the number. You can see that when Chinese people choose a number for their telephone, 4 and 7 are most disliked by them.
Meanings for Other Numbers: 0, 1, 2, 3, 5
Zero - Means everything or nothing. It is limitless. Chinese people think everything begins with 0.
One – means the first. It is the simplest number but also the most complex one in terms of its cultural meaning in Chinese culture. It is neither auspicious nor inauspicious. People use it to name the winner. It also has the meaning of beginning, loneliness, single. For example: November 11^th is the single’s day in China, as the date has four ‘1’ which stand for single.
Two - means ‘double’, ‘twinned’ and ‘again’. In most cases, it is a lucky number in Chinese culture as Chinese people think all good things com in pairs. But in some areas, people use this number to describe someone is stupid and reckless which is ironic.
Three – is a lucky number in Chinese culture as it sounds similar to the character of ‘birth’ (生 shēng). For a people’s life, there are three most important stages: birth, marriage and death. You can see the number 3 is greatly used in Chinese culture, history and more: There are three gorges of Yangtze River; Three Sages and Three Kingdoms in Chinese history; three halls of Forbidden City in Beijing…
Five – a neutral number in Chinese culture. It is lucky as it usually related to the Emperor of China. There are five blessings in China - wealth, happiness, longevity, luck and prosperity. Also in Chinese astrology, there are five elements - Metal, Wood, Water, Fire and Earth. There are Five Kinds of Main Grain in China. As it has the same pronunciation with ‘无’（means nothing in Chinese）, it has a negative meaning. It also used to mean ‘I’ because of the similar pronunciation with ‘我’ in Chinese.