A whole number less than ten; = digit, n. 1a. Cf. articulus, n. 1.

Astronomy and Mathematics. The angle, arc, or other mathematical quantity, from which another required quantity may be deduced, or on which its…

Mathematics. In S. Jeake's terminology: a concrete number (cf. sense A. 2). Obsolete. rare.

(a) Mathematics a quantity (quantity, n. 3a) in an equation, etc., whose value is known; (b) figurative something or someone whose nature or…

either of a pair of numbers, each of which equals the sum of all the factors of the other, excluding the number itself; = amiable number n. at amiable…

With reference to an infinite series (series, n. 8): the property or fact of being summable (summable, adj. 1b).

An idempotent element.

Mathematics. The property of being modular (modular, adj. 1).

A number consisting of a sequence of 1s or the single digit 1. Also repunit number.

In extended use. A number, or a date expressed numerically, that is unchanged when the order of its digits is reversed.

Mathematics. A number or vector used as an initial value in an algorithm, esp. for the purpose of generating a sequence of pseudorandom numbers.