The results of the calculation of the electronic and magnetic properties for the spin-gapped material CuTe2O5 are presented. The direct computation of exchange constants J in the framework of the LDA + U shows that the largest exchange coupling in CuTe2O5 is found between fourth nearest neighbors, as was argued by Das et al (2008 Phys. Rev. 77 224437), and that this compound should be considered as the two-dimensional coupled dimer system.