Meat has a specific heat of about 3.5kJ per kilo per degree, so say you weigh 70kg, that’s about 4 million joules to lose before you die.

At 650 joules per second, you’ve got slightly over 10 minutes.

My man, first of all

4,000,000/650/60=102.57 minutes

And that’s with your math based on an imaginary object. A body is going to lose heat far more slowly.

Also, you forgot one important aspect, if you’re getting bathed by the sun and spinning, you’re constantly getting heated up.