My math seems to indicate 41,187 days. But I am not understanding what you mean here. There were 4660 days between January 1 1900 and October 5 1912 that he did not live through, so the number of days he lived since January 1 1900 will be the same as the number of days he has lived since he was born.
I think the math was correct but the English was not. I changed the wording in my post to try to correct that.