Is 6,500 SGD is enough for single person in Singapore?

You are asking two independent questions:
1. Whether the offered salary is fair for the job, and
2. Whether the money is enough to survive?
Regarding the first, you should consult salary survey, which are published by various consultancies in regular intervals.
Regarding the second: This is above the average household income in Singapore - so if you cannot manage on it as a single person, you should adjust your lifestyle and spending choices.

Hi Beppi,

Thanks for replying.
For question no. 2,Considering i am expat...Is it enough as i would have to travel to India once in a year?

As I implied, it all depends on your lifestyle and spending habits - it is easy to spend it all and still want more. But the average Singaporean family (of three people) manages with it.