Numeric Value: 40

The folowing table expresses '40' in various number bases. 'DRx' shows the result of 'digit reducing' resulting in an X-digit long number.

BaseDR6DR5DR4DR3DR2DR1
2101000   101
3  1111 112
4   220101
5   130 4
6   104 5
7    55,134
8    505
9    448
10    404
11    37A
12    347
13    314
14    2C,101
15    2AC
16    28A

Math World

Factors: 23 * 5

40 is in the Pythagorean Triples: (9, 40, 41), (40, 399, 401).

A 'Tetracontagon' is a 'regular polygon' with 40 sides.

Physical World

40 is the atomic weight of Zirconium (Zr).