Search a number
unprimeable n.  and  upside-down n.

First numbers that belong to both sets:

2198, 2828, 4196, 4556, 4826, 5375, 5465, 5915, 6644, 8552, 8912, 22588, 23578, 24568, 25558, 26548, 28528, 29518, 49516, 53575, 55555, 57535, 58525, 61594, 69514, 81592, 82582, 84562, 85552, 86542, 215598, 218298, 219198, 231978, 238278, 249168, 251958, 252858, 256458, 261948, 262848, 263748, 268248, 272838, 274638, 291918, 294618, 296418, 413796, 415596, 417396, 418296, 425586, 428286, 431976, 432876, 434676, 437376, 441966, 444666, 447366, 448266, 451956, 454656, 457356, 458256, 459156, 461946, 467346, 473736, 474636, 475536, 476436, 477336, 478236, 481926, 485526, 486426, 487326, 491916, 492816, 496416, 497316, 498216, 513795, 514695, 523785, 532875, 538275, 542865, 545565, 554655, 557355, 567345, 575535, 578235, 585525, 587325, 591915, 592815, 597315, 612894, 613794, 616494, 617394, 618294, 619194, 623784, 629184, 632874, 633774, 635574, 638274, 639174, 643764, 645564, 646464, 649164, 651954, 653754, 654654, 657354, 663744, 664644, 666444, 667344, 669144, 672834, 673734, 674634, 676434, 678234, 679134, 681924, 682824, 683724, 684624, 685524, 687324, 689124, 692814, 693714, 695514, 697314, 698214, 812892, 817392, 819192, 821982, 825582, 826482, 828282, 831972, 833772, 835572, 838272, 839172, 841962, 844662, 846462, 854652, 855552, 859152, 862842, 865542, 869142, 872832, 875532, 881922, 884622, 888222, 891912, 895512, 899112, 2115998, 2125898, 2145698, 2165498, 2235788, 2265488, 2275388, 2285288, 2295188, 2315978, 2335778, 2345678, 2355578, 2375378, 2385278, 2415968, 2425868, 2435768, 2445668, 2485268, 2565458, 2615948, 2625848, 2655548, 2665448, 2755538, 2775338, 2785238, 2795138, 2835728, 2845628, 2855528, 2875328, 2885228, 2915918, 2955518, 2995118, 4115996, 4135796, 4155596, 4165496, 4175396, 4185296, 4195196, 4215986, 4225886, 4245686, 4285286, 4315976, 4335776, 4345676, 4365476, 4375376, 4385276, 4425866, 4465466, 4475366, 4485266, 4495166, 4515956, 4525856, 4535756, 4545656, 4565456, 4575356, 4585256, 4595156, 4615946, 4635746, 4655546, 4685246, 4715936, 4745636, 4765436, 4795136, 4815926, 4825826, 4845626, 4855526, 4865426, 4885226, 4895126, 4915916, 4925816, 4995116, 5115995, 5125895, 5135795, 5145695, 5155595, 5175395, 5185295, 5195195, 5215985, 5225885, 5235785, 5245685, 5255585, 5295185, 5325875, 5365475, 5385275, 5395175, 5425865, 5435765, 5445665.

Some larger examples :