2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/215925We show that, if g is more than or equal to 2, the virtual cohomological dimension of the mapping class group of a 3-dimensional handlebody of genus g is equal to 4g-5 and the Euler number of it is equal to 0.8 pages, 1 figureGeometric TopologyGroup Theory57N10, 57N05, 20F38text