Castle Grant, in Grantown on Spey, was repossessed by the Bank of Scotland last week over mortgage arrears.
It has a ballroom, cinema room, billiards room, a library, four bedrooms and a guest wing. The four-storey castle also has a landscaped loch and 35 acres of private land.
The sale is being handled by estate agents Strutt and Parker in Inverness.
The castle was redeveloped in the 1990s before it was sold to Mr Whyte but is now said to need "significant investment" - although the estate agency said it could be "one of the premier private houses in the UK".
Most of Mr Whyte's belongings were removed from the property last week.
Estate agent Kevin Maley said: "It is clear that a number of improvements have been made, however a large part of the property remains undeveloped and a significant amount of investment will be required to finish this off.
"Castle Grant is a wonderful property which is absolutely ripe for development which could lead to it being one of the premier private houses in the UK."
Mr Whyte bought Rangers in 2011 while a large tax liability was in dispute. The club went into administration less than a year later and was eventually liquidated.
In December, he lost an appeal over a court ruling that he must pay £17.6 million to ticketing firm Ticketus who provided funds to help buy the club under a deal which would see it paid back from ticket sales.