A half wave dipole capable of radiating 1 kW and has 2.15

A half wave dipole capable of radiating 1 kW and has 2.15 dB over a isotropic antenna. How much power must be delivered to the isotropic omnidirectional antenna, to match the field strength of directional antenna?

Given P₁ = 1 kW (Power of unidirectional antenna)
P₂ =? (Power delivered)
Gain in dB = 2.15
Now,

2.15 = 10 log₁₀		P₂
		1000

or
P₂ = 1000 × 10^.215
or
P₂ = 1640. 589
or
P₂ ≈ 1641 watt