The correct number is 879,136 valid signatures. That is 12% (from Article 2, Section 14(b) of the California Constitution) of the 7,326,133 people who voted for Governor this past November.
Therefore it is reasonable to aim for 1.2 million raw signatures, which would meet the target even if the validity rate was only 73%. Getting that many raw sigs also makes it likely that they could be validated through a sampling procedure, which would speed up the recall election by several weeks.
Even Shawn Steele and his merry band of screw-ups should be able to double that with the kind of dollars they have access to.