What type of number is - 1

-1 is an integer, rational number and negative number

Step-by-step explanation:

An integer is any number that is on the number line that is a whole number.

For example: 1, - 2, and 3 are all integers, but 3/5 is not a integer

It is also a rational number since it can be expressed as a ratio: - 1/1

However, square roots and pi are not rational numbers

Negative numbers are all numbers to the right of zero.

The number - 1 is a negative number.