The others have pointed out many things, but I have one thing to add:

Instead of using the + operator for accumulating a total, thus having to write the left-hand operand twice, you can use the += operator instead.

For instance, instead of

number = number + 2;

you'll have

number += 2;

The relevant statements would look like this. I'll also apply some of @palacsint's suggestions so that you can see the improved code together.

for (double x = 1; x > 0.000; x += 1.000) {
    // ...
    for (double multiplier = 1.000; multiplier <= (x); multiplier += 1.000) {
        // ...
        primeLogger += 1.000;
        // ...
    }
}

The others have pointed out many things, but I have one thing to add:

Instead of using the + operator for accumulating a total, thus having to write the left-hand operand twice, you can use the += operator instead.

For instance, instead of

number = number + 2;

you'll have

number += 2;

The relevant statements would look like this. I'll also apply some of @palacsint's suggestions so that you can see the improved code together.

for (double x = 1; x > 0.000; x += 1.000) {
    // ...
    for (double multiplier = 1.000; multiplier <= (x); multiplier += 1.000) {
        // ...
        primeLogger += 1.000;
        // ...
    }
}

Although those three variables should just be incremented by one with ++ (based on @Uri Agassi's advice), I've shown the use of += here just for demonstration. For values other than one (which only works with ++ or --), you would use +=.