Substring operation in kshell

Shell Programming and Scripting
1

Hi,
Please let me know how to perform the substring operation in kshell.
If i have line like below
238923893282389034893489458945904589045454903490

i would like to retrieve the position 7 to 19, how to do this in kshell?

2 
$ echo 238923893282389034893489458945904589045454903490 | cut -c7-19
8932823890348