Writing a number in standard form simply means to express the number in its 'normal' form. Therefore, your example is written in standard form.
1213
It is 1213.
How do write 666 in standard form?
That is the standard form!
It is already in standard form.
1213
1213 x 246565 = 299083345
It is 1213.
Stephen Langton was the Archbishop of Canterbury in 1213.
1213+356 = 1569
It is already in standard form.
9,670 is the standard form.
How do write 666 in standard form?
That is the standard form!
what is the standard form of 13.088?
It is already in standard form.
It is already in standard form.