Dart Number
The Number is the data type that is used to hold the numeric value. In Dart, It can be two types 
Dart integer  Integer numbers are the whole numbers means that can be written without a fractional component. For example  20, 30, 3215, 0, etc. An integer number can be signed or unsigned. The representation of the integer value is in between 263 to 263 nondecimal numbers. The int keyword is used to declare integer value in Dart.
Dart Double  The Double number are the numbers that can be written with floatingpoint numbers or number with larger decimal points. The double keyword is used to declare Double value in Dart.
Rules for the integer value
 An integer value must be a digit.
 The decimal points should not include in an integer number.
 Unsigned numbers are always a positive number. Numbers can be either negative or positive.
 The size of the integer value depends upon the platform, but integer value should no longer than 64 bit.
Let's have a look at following example 
Example 
Output:
Dart parse() function
The parse() function converts the numeric string to the number. Consider the following example 
Example 
Output:
Explanation 
In the above example, we converted the numeric strings into the numbers by using parse() method then stored in the variables. After the successful conversion, we performed add operation and printed the output to the screen.
Number Properties
Properties 
Description 
hashcode 
It returns the hash code of the given number. 
isFinite 
If the given number is finite, then it returns true. 
isInfinite 
If the number infinite it returns true. 
isNan 
If the number is nonnegative then it returns true. 
isNegative 
If the number is negative then it returns true. 
sign 
It returns 1, 0, or 1 depending upon the sign of the given number. 
isEven 
If the given number is an even then it returns true. 
isOdd 
If the given number is odd then it returns true. 
Number Methods
The commonly used methods of number are given below.
Method 
Description 
abs() 
It gives the absolute value of the given number. 
ceil() 
It gives the ceiling value of the given number. 
floor() 
It gives the floor value of the given number. 
compareTo() 
It compares the value with other number. 
remainder() 
It gives the truncated remainder after dividing the two numbers. 
round() 
It returns the round of the number. 
toDouble() 
It gives the double equivalent representation of the number. 
toInt() 
Returns the integer equivalent representation of the number. 
toString() 
Returns the String equivalent representation of the number 
truncate() 
Returns the integer after discarding fraction digits. 
