The Octal number to be given alogn with chmod command to make a file readable, writable and executable to the owner, readable and executable to group and others is:

For the owner to have read, write, and execute permissions (7 = 4 + 2 + 1). For the group and others to have read and execute permissions (5 = 4 + 1). So, the octal number to be given along with the chmod command to achieve these permissions is 755.