This online mathematical keyboard is limited to what can be achieved with Unicode characters. However to type this symbol in MS Word just type 00B2 select it and then press Alt X to g. Text Shortcuts on iOS.
The exponent of a number says how many times to use the number in a multiplication.
To add an exponent symbol after a number or letter when using a Windows operating system the alt key should be held down and the code 0176 0185 0178 or 0179 should be pressed. Sometimes E is also used to show exponent for the power of 10. B raised to the n-th power b raised to the power of n or b raised by the exponent of n most briefly as b to the n. This means for example that you cannot put one symbol over another.