What is 778,400,000 in scientific notation?

When working with very large or very small numbers, scientists, mathematicians, and engineers use scientific notation to express these quantities. Scientific notation is a mathematical abbreviation, based on the idea that it is easier to read an exponent than to count many zeros in a number. Very large or very small numbers need less space when written in scientific notation because the position values ​​are expressed as powers of 10. Calculations with long numbers are easier to do when using scientific notation

First of all, this could be easily done with a calculator but it's 7.8^8

were is the equation