Numeric Value: 90

The folowing table expresses '90' in various number bases. 'DRx' shows the result of 'digit reducing' resulting in an X-digit long number.

BaseDR7DR6DR5DR4DR3DR2DR1
21011010   100 1
3  10100   2
4   1122 123
5    330112
6    230 5
7    156156
8    132 6
9    110 2
10     909
11     82A
12     76,112
13     6C,156
14     66C
15     606
16     5AF

Math World

Factors: 2 * 32 * 5

90 is the interior angle of a 'Square (or Tetragon)' (see 'regular polygons').

A 'Enneacontagon' is a 'regular polygon' with 90 sides.

Physical World

90 is the atomic weight of Thorium (Th).