[General] "a half million" or "half a million"

[Olympian]

Hello,

I was watching a program called "Minute to Win It" on TV. On it the host said: "Watch them win a half million dollars". The subtitles also said it exactly like this, so I know that I did not make a mistake in hearing it.
Is it correct to say "a half million dollars"? Or should it be "half a million dollars"? Before this I have only heard "half a million dollars". So now I am a bit confused.

Thank you

 

[5jj]

half a is more common, but a half is acceptable.

 

[Olympian]

Thank you fivejedjon.