2471 px = 12,742 km
154 px = 794.11898 km
R = 397.059 km
Since it's an actual nuclear explosion I'll use the Fireball Radius in this calculator.
Y = 25,560,000 Megatons or 25.56 Teratons of TNT
Kenshiro could easily hurt Jagi in base form and his 100% mode is 3.333 times stronger. In his rematch with Kaioh, his base form was stronger than his previous 100% mode (which was previously defeated by Kaioh).
Base Kenshiro = 25.56 Teratons
100%/New base = 85.2 Teratons
New 100% Kenshiro = 284 Teratons