The word coefficients is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 25
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (29 words)
cenotes, coesite, coffees, coffins, conceit, concise, confect, confits, effects, entices, eosinic, fiction, fifteen, fifties, iconist, incites, infects, inosite, notices, octenes, offence, offense, offices, offsite, science, section, stiffen, toffees, toffies