(Java) what happens when we declare an int and assign it a value which start with 0?

Question

For example:

int a = 065;
System.out.println(a)

Why output is 53?

Answer 1

When you write zero in front of a number, then the number is treated as octal number.
065octal = 6*8^1 + 5*8^0 = 53decimal

Answer 2

voja thanks now I understand