If you mean how to write 7 in Chinese character, it is 七。
But in general, 7 is not a so welcomed number to most of Chinese people. Part of the reason is that 7(qī)has the same pronounciation with the character "气"(qì) which mean anger. So people don't want to choose a mobile number which will bring troubles and anger to themselves.
七 chee
The cross bar in the number 7 is used to make it easier to distinguish from the number 1. When they are written clearly, 7 and 1 do not really look the same, but some people make the serif on top of the 1 too large, and it starts to look like a 7.
The absolute value of that number, like -7-0= |-7| or just 7.
7/13 < 75/125 < 16/18
looks like a 7, right?
As a number it is: 7,000,000,000
七 chee
7 is called na-na(In kanji 七) in japanese.
The cross bar in the number 7 is used to make it easier to distinguish from the number 1. When they are written clearly, 7 and 1 do not really look the same, but some people make the serif on top of the 1 too large, and it starts to look like a 7.
Like this
The absolute value of that number, like -7-0= |-7| or just 7.
7 x 7 = 49
7/13 < 75/125 < 16/18
looks like a 7, right?
7 is the mixed number, because 7/1 is like saying 7 wholes. So its 7.
it would just be 7 times 'a' minus 6 so it would look like this: 7a-6
7 lines put together