Which network is 74666 in United Kingdom?

This range is shared across prefixes: 74040, 74041, 74042, 74043, 74044, 74045, 74046, 74047, 74048, 74049, 74050, 74051, 74052, 74053, 74054, 74055, 74056, 74057, 74058, 74059, 74173, 74174, 74175, 74240, 74241, 74242, 74243, 74244, 74245, 74246, 74247, 74248, 74249, 74380, 74381, 74382, 74383, 74384, 74385, 74386, 74387, 74388, 74389, 74400, 74401, 74402, 74403, 74404, 74405, 74406, 74407, 74480, 74481, 74482, 74483, 74484, 74485, 74486, 74487, 74488, 74489, 74590, 74591, 74592, 74593, 74594, 74595, 74596, 74597, 74598, 74599, 74660, 74661, 74662, 74663, 74664, 74665, 74666, 74667, 74668, 74669