Check whether digits of an integer has an increasing sequence

Given an integer, check whether digits of the integer has an increasing sequence.

Sample Code:

function isIncreasing(number) {
// Enter your logic here...
}

Examples:

Input: 1234
Output: true
Explanation: 1,2,3,4 is an increasing sequence.

Input: 2571
Output: false
Explanation: 2,5,7,1 is not an increasing sequence.