A number one single is used to distinguish it from a number one album,which is a collection of singles.

A number one single is the same as a number one hit

One is not a prime number. A prime number, by definition, is a number that is only divisible by two numbers: one and itself. One is divisible by only one number, one, and therefore is not a prime number.

you are number one

The sum of one odd number and one even number is another odd number.

There is only one number: 346913. One number does not provide enough information about a sequence.

There is only one number: 346913. One number does not provide enough information about a sequence.

There is only one number: 346913. One number does not provide enough information about a sequence.

There is only one number: 346913. One number does not provide enough information about a sequence.