为什么有错误

public class Demo {

public String name;

public String brithday;

public int number;

public void setName(String name){

this.name=name;

}

public void setBrithday(String brithday){

this.brithday=brithday;

}

public void setNumber(int number){

this.number=number;

}

public String getName(){

return this.name;

}

public String getBrithday(){

return this.brithday;

}

public int getNumber(){

return this.number;

}

public static void main(String[]args){

Demo student=new Demo();

student.setName("杨");

student.setBrithday("1996-11-11");

student.setNumber("1408441063"); //这里报错

System.out.println(student.getName());

System.out.println(student.getBrithday());

System.out.println(student.getNumber());

}

}