Letters that make opposite number
s, o, b, e, n, p, m, r, t, i, u are letters that make 'opposite number'
Words within opposite number
ER, number, os, OS, IT, site, MB, posit, te, si, PO, nu, sit, be, SI, numb, umber, opposite, Mb, Po, Be, Er, Os, Si, Te are words within 'opposite number'