Every culture is characterised by a particular numerical symbolism which often differs from that of other regions.
There are many reasons why some numbers are considered lucky and why some numbers are unlucky. Some of the reasons are due to superstitious and some could be due to folklore, legends, religious traditions, etc.
The common unlucky number in most countries is the number 13. This is because it could be due to biblical connotations such as 13 people at the last supper and even, thirteen members of a historic witch coven. At some hotels and even apartments and condominiums, the number 13 is completely omitted.
Some countries such as U.K, U.S.A., France and The Netherlands consider the number 7 to be lucky as again, there is some biblical reference when God created the universe in 7 days, the week also has 7 days. Some believe it is because of the 7 wonders of the ancient world and even because of the 7 ancient planets.
Norway, on the other hand, considers numbers 9 and 13 to be lucky due to mythology believes. In Sweden, they believe the number 3 is be lucky as all good things come in the group of 3. Russians believe that 000 is lucky and even numbers are unlucky.
Whatever the reason why numbers are considered to be lucky, in some ways, each person has their own superstitions and quirks. To some people, a certain number may be lucky whilst that same number will be unlucky to others. To each his own, in that sense.
It is good knowledge to know what are lucky and unlucky numbers as it’s good for general knowledge, especially when you go travelling. It will help you understand the culture of the country you’re visiting better and also help you avoid taboos or offending someone.