①最后只有一位是0,即10-90,110-190,210-290,310-390,410-490,510-590,610-690,710-790,810-890,910,一共是82个0;
②最后两位都是0,即100、200、300、400,500,600,700,800,900一共是18个0;
③中间是0,101-109,201-209,301-309,401-409,501-509,601-609,701-709,80-809,一共是72个;
综上,总共82+18+72=172个0.
故答案为:172.