concatenate two columns of numbers does not produce concatenated value

Hi,

i am enclosing excel macro which basically has 3 cols..........the third col is basically a concatenation of the first two cols where both cols are numbers. The resultant column is a number but its not the "TRUE" concatenated value........

any ideas?

example:
ColA= 20070337
ColB= 10002
ColC= 2.00703E+12


i want col C to equal 2007033710002