I want to know:For Example:how many digits 10! is without calculate it I need a formula to count for any Integer.Is there formula to calculate the digits of any Integer number?
[Math] Factorial Length
factorial
factorial
I want to know:For Example:how many digits 10! is without calculate it I need a formula to count for any Integer.Is there formula to calculate the digits of any Integer number?
Best Answer
Working in the decimal system you need to take the logarithm with base $10$, round down and add 1.
For $10!$ the number of digits is therefore $\left \lfloor \log_{10} (10!) \right \rfloor + 1$.