20亿以内哪个数的约数个数最多，个数是多少？

混蛋的百度吞了我好几条答案。

于是我在这里发下：是1536

这里在贴一下部分评測数据，为什么是部分呢？由于是在非常多台电脑上跑的。丢了一些。可是肯定跑全了！

答案是没有错的。

嗯，有好几个数的约数个数都是1536。

额。我还是先贴一下评測代码吧。

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
#define N 15
int ans=0;
int p[N],cnt;
int main()
{
	int i,j,k;
	for(i=1029188160;i<=2000000000;i++)
	{
		cnt=0;
		k=i;
		for(j=2;j*j<=k;j++)
		{
			if(k%j==0)
			{
				p[++cnt]=0;
				while(k%j==0)
				{
					p[cnt]++;
					k/=j;
				}
			}
		}
		if(k>1)p[++cnt]=1;
		int temp=1;
		for(j=1;j<=cnt;j++)
		{
			temp*=(p[j]+1);
		}
		if(ans<temp)
		{
			printf("%d : %d\n",i,ans=temp);
		}
		if(i%10000000==0)printf("%d at %d\n",temp,i);	
	}
	printf("%d\n",ans);
	system("pause");
	return 0;
}

1029188160 : 1344
128 at 1030000000
176 at 1040000000
288 at 1050000000
144 at 1060000000
128 at 1070000000
320 at 1080000000
128 at 1090000000
162 at 1100000000
1102701600 : 1440
256 at 1110000000
192 at 1120000000
128 at 1130000000
288 at 1140000000
144 at 1150000000
160 at 1160000000
384 at 1170000000
144 at 1180000000
256 at 1190000000
198 at 1200000000

1200000000 : 198
198 at 1200000000
1200000528 : 240
1200001440 : 384
1200003840 : 432
1200009600 : 768
1200119760 : 960
1200719520 : 1152
192 at 1210000000
1210809600 : 1296
144 at 1220000000
1225224000 : 1344
256 at 1230000000
1232431200 : 1440
160 at 1240000000
88 at 1250000000
432 at 1260000000
128 at 1270000000
120 at 1280000000
256 at 1290000000
162 at 1300000000

1400000000 : 180
180 at 1400000000
1400000085 : 192
1400000448 : 224
1400000616 : 288
1400001408 : 480
1400011200 : 1008
1401079680 : 1024
1401472800 : 1152
1403438400 : 1260
1409007600 : 1440
256 at 1410000000
144 at 1420000000
256 at 1430000000
288 at 1440000000
144 at 1450000000
144 at 1460000000
384 at 1470000000
1470268800 : 1536
160 at 1480000000
128 at 1490000000
180 at 1500000000

1500000000 : 180
180 at 1500000000
1500000480 : 288
1500001360 : 320
1500001800 : 384
1500003120 : 480
1500004800 : 504
1500012000 : 768
1500127200 : 864
1500206400 : 1008
1500899400 : 1152
1504198080 : 1344
128 at 1510000000
176 at 1520000000
384 at 1530000000
288 at 1540000000
1543782240 : 1440
144 at 1550000000
320 at 1560000000
128 at 1570000000
144 at 1580000000
256 at 1590000000
117 at 1600000000
256 at 1610000000
360 at 1620000000
128 at 1630000000
160 at 1640000000
1643241600 : 1536
288 at 1650000000
144 at 1660000000
128 at 1670000000
352 at 1680000000
192 at 1690000000
162 at 1700000000

1700000000 : 162
162 at 1700000000
1700000064 : 168
1700000120 : 192
1700000610 : 256
1700000640 : 384
1700005440 : 448
1700006000 : 480
1700013600 : 648
1700028000 : 672
1700047440 : 720
1700075520 : 768
1700099280 : 800
1700206200 : 960
1700233920 : 1008
1700899200 : 1152
1706443200 : 1176
1709187480 : 1280
384 at 1710000000
1715313600 : 1512
160 at 1720000000
128 at 1730000000
288 at 1740000000
1745944200 : 1536
160 at 1750000000
192 at 1760000000
256 at 1770000000
144 at 1780000000
128 at 1790000000
270 at 1800000000

1800000000 : 270
270 at 1800000000
1800001500 : 288
1800001632 : 384
1800002160 : 480
1800005760 : 512
1800009120 : 576
1800014400 : 840
1800136800 : 864
1800152640 : 896
1800179640 : 960
1800691200 : 1080
1801079280 : 1280
1807565760 : 1344
128 at 1810000000
1816214400 : 1440
288 at 1820000000
256 at 1830000000
1837836000 : 1536
176 at 1840000000
144 at 1850000000
288 at 1860000000
256 at 1870000000
160 at 1880000000
512 at 1890000000
162 at 1900000000
128 at 1910000000
224 at 1920000000
128 at 1930000000
144 at 1940000000
288 at 1950000000
240 at 1960000000
128 at 1970000000
432 at 1980000000
128 at 1990000000
110 at 2000000000
1536