[著者版] ; arXiv:0710.4590v2 [astro-ph] http://arxiv.org/abs/0710.4590 ; The long, bright gamma-ray burst GRB 070125 was localized by the Interplanetary Network. We present light curves of the prompt gamma-ray emission as observed by Konus-Wind, RHESSI, Suzaku WAM, and Swift BAT. We detail the results of joint spectral fits with Konus and RHESSI data. The burst shows moderate hard-to-soft evolution in its multipeaked emission over a period of about 1 minute. The total burst fluence as observed by Konus is 1: 79; 10(-4) ergs cm(-2) (20 keV-10 MeV). Using the spectroscopic redshift z = 1.548, we find that the burst is consistent with the "Amati'' E-peak,(i)-E-iso correlation. Assuming a jet opening angle derived from broadband modeling of the burst afterglow, GRB 070125 is a significant outlier to the "Ghirlanda'' E-peak,(i)-E-gamma correlation. Its collimation-corrected energy release, E-gamma = 2.5 x 10(52) ergs, is the largest yet observed.