assign numeric data type to user variable

how to pass the column that has a numeric(12,0) data type to user variable in SSIS? what kind of variable data type should I choose?
if i select int64, it keep giving me an error:
Error: 0xC001F009 at Row by Row process: The type of the value being assigned to variable "User:bject_Key" differs from the current variable type. Variables may not change type during execution. Variable types are strict, except for variables of type Object.

there is no numeric data type in variable..

if you click the drop down box in variable data type, you can only see the below data type:

Int32
int64
Object
Sbyte
single
string
uint32
uint64
boolean
byte
char

Do some searching on this forum. It has been discussed in just the last week, along with several other occasions. You'll likely have to read it in as a string and then later convert it to an integer using variable expressions.|||thank you