Hey there J,
Sooooo first of all (and I guess you know this), with your GMAT the schools you listed are pretty much out of range. They take like one or maybe two people with a GMAT of 640 every year, and those candidates are like super-psycho-crazy strong! So, first piece of advice to you: retake your GMAT!
If you can hit a 700 or above, then you can be comfy!
Also, if you want a full on evaluation, I need a LOT more info from you dude, like, what positions you held, how many promotions you got, how many people you led, whether you have international experience or not, what sort of other leadership experience you have, more info about ECs and volunteer work, etc. etc.
All of these things go into building a full profile, and the schools you apply to will look at all of them,
Hope this helps you out dude,
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