That’s off by a bit:

600 years * 365 days/year * 24 hours/day * 60 minutes/hour = 315,360,000 minutes

315,360,000 minutes * $1,000,000,000/minute = $315,360,000,000,000,000 or $315 Quadrillon

For Musk:

$225.5B current NW

$225,500,000,000 / 315,360,000 minutes = $715/minute