I'm going with a male. Those tail feathers are way to steep and tall for a hen. Or at least any hen I've seen. You can also send pictures when his tail is down. Here's some photos to help out. Sorry it took me a while.
See how the webbing of the feather is all wispy? That's a sign for males. Along with the steep tall tail feathers.
Here's White peahen neck feathers. The feather is more solid instead of looking like hair.
Here's a White peacock neck feathers.
Just so you can see better. Indian Blues and Whites' neck feathers are the same structure. See the male is kind of like a hair like quality.
Hen is more solid feather.
Peacock is closest peahen is in the back. Looking at the tail coverts and premature train you can see some differences. Tail coverts are more of a solid feather and not wispy like the premature train on the peacock. I hope this helps with sexing white peafowl.