−1 - Wikipedia −1 📊 ➺ 📊 ➺ 📊 ➺ 📊 ➺ In mathematics, −1 (negative one or minus one) is the additive inverse of 1, that is, the number that when added to 1 gives the additive identity element, 0. It is the negative integer greater than negative two (−2) and less than 0. Printed 2026-06-28. (echo:: @ ᯤ)