Four playful mathematicians were eating lunch together at an outdoor cafe. They noticed a diamond-encrusted Rolex had been left behind at the table next to them, so they quickly looked around for the person who had vacated the table. They saw the owner of the watch driving away. "Quick, get the license plate!" urged one of the mathematicians, seeing that it was only a four-digit number. When the car had disappeared around the corner, they put together these characteristics they'd noticed about the number:

The first said, "One of the digits is neither prime nor composite."
The second contributed, "The digit in the hundreds place is three times the digit in the thousands place."
The third added, "The digit in the ones place is four times greater than the digit in the tens place."
The fourth piped up with the last bit of information. "The smallest prime number is in the thousands place. We have enough information to help us locate the owner of the watch."
What number did the four playful mathematicians see on the license plate?