Is there an organizer for Windows with GTD features and a built-in email client?

Question

Task Management

Good afternoon!
Please tell me if there is a desktop organizer with the following functions:

• work with incoming and outgoing mail
  
• the ability to work with letters as with tasks
  
• creating projects, categories,
  
• the ability to create subtasks of any nesting
  
• task highlighting in different colors
  
• ability to measure task execution time
  
• desktop application for Windows
  
• the ability to synchronize with the cloud or with dropbox-storage (the ability to work simultaneously on 2 PCs)
  
• contact lists
  
• categorized notes
  

Ready to consider paid options.

Answer 1

IBM Lotus Notes :-|

Answer 2

1/ mail is usually the biggest distraction
2/ write a proposal to the authors of LeaderTask, EssentialPIM, etc.

Answer 3

MS Outlook can do all of the above, except for nested subtasks.