Hey Vivek, 

   The cutoff is determined by many factors. Some of them are:

•  Previous year cutoff trends

• Number of available seats in the programme. 

• Difficulty level of GATE 2019

• Total number of candidates who registered for the exam.

Since you are a general category student, it is a quite tough to get into IITs, but it is quite a good score, so considering it, I've shortlisted the following colleges according to previous year cutoffs.

• IIT Guwahati(>=600)
• IIT Hyderabad research ass. (658)
• NIT Durgapur(698)
• MNIT Jaipur(703_725)
• 
  
• MANIT Bhopal (607-715)
• Motilal Nehru National Institute of Technology allahabad (682-726) 
• Indian Institute Of engineering an science (559-720)
• Iiit allahabad (706)

These are some of the best institutes of the country and you are quite eligible for all of them. 

Hope it helps. 

Thankyou 

Hello Vivek, 

Congratulations to you for obtaining such a good marks. According to the prediction of your score, your predictable rank would lie between 335-565. You can explore your career opportunities in old IITs, new IITs, top NITs and top state level colleges. 

Good luck...