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

First numbers that belong to both sets:

1919, 2828, 3737, 4646, 5555, 6464, 7373, 8282, 9191, 16549, 35557, 133779, 149169, 162849, 178239, 191919, 227388, 243768, 266448, 282828, 289128, 313797, 323787, 333777, 343767, 353757, 363747, 373737, 383727, 393717, 412896, 427386, 464646, 479136, 511995, 522885, 533775, 544665, 555555, 566445, 577335, 588225, 599115, 629184, 646464, 663744, 737373, 828282, 831972, 887322, 919191, 927381, 935571, 943761, 951951, 1155599, 1475369, 1625849, 1795139, 1945619, 2225888, 2295188, 2475368, 2655548, 2835728, 3315977, 3425867, 3535757, 3645647, 3755537, 3865427, 3975317, 4335776, 4495166, 4745636, 7455563, 8555552, 11219899, 11373799, 11664499, 11955199, 12346789, 12637489, 12791389, 12928189, 13182979, 13319779, 13473679, 13764379, 14155969, 14446669, 14737369, 14891269, 15128959, 15282859, 15419659, 15573559, 15864259, 16255849, 16546549, 16837249, 16991149, 17228839, 17382739, 17519539, 17673439, 17964139, 18355729, 18646429, 18937129, 19191919, 19328719, 19482619, 19619419, 19773319, 22128988, 22191988, 22273888, 22355788, 22437688, 22519588, 22582588, 22664488, 22746388, 22828288, 22891288, 22973188, 24173968, 24255868, 24337768, 24419668, 24482668, 24564568, 24646468, 24728368, 24791368, 24873268, 24955168, 26155948, 26237848, 26319748, 26382748, 26464648, 26546548, 26628448, 26691448, 26773348, 26855248, 26937148, 28137928, 28219828, 28282828, 28364728, 28446628, 28528528, 28591528, 28673428, 28755328, 28837228, 28919128, 28982128, 31119997, 31219897, 31319797, 31419697, 31519597, 31619497, 31719397, 31819297, 31919197, 32128987, 32228887, 32328787, 32428687, 32528587, 32628487, 32728387, 32828287, 32928187, 33137977, 33237877, 33337777, 33437677, 33537577, 33637477, 33737377, 33837277, 33937177, 34146967, 34246867, 34346767, 34446667, 34546567, 34646467, 34746367, 34846267, 34946167, 35155957, 35255857, 35355757, 35455657, 35555557, 35655457, 35755357, 35855257, 35955157, 36164947, 36264847, 36364747, 36464647, 36564547, 36664447, 36764347, 36864247, 36964147, 37173937, 37273837, 37373737, 37473637, 37573537, 37673437, 37773337, 37873237, 37973137, 38182927, 38282827, 38382727, 38482627, 38582527, 38682427, 38782327, 38882227, 38982127, 39191917, 39291817, 39391717, 39491617, 39591517, 39691417, 39791317, 39891217, 39991117, 41237896, 41382796, 41755396, 42328786, 42473686, 42846286, 42991186, 43191976, 43419676, 43564576, 43937176, 44137966, 44282866, 44655466, 45228856, 45373756, 45746356, 45891256, 46319746, 46464646, 46837246, 46982146, 47182936, 47555536, 47928136, 48128926, 48273826, 48646426, 48791326, 49219816, 49364716, 49737316, 49882216, 51155995, 51264895, 51373795, 51482695, 51591595.

Some larger examples :