145 (number)
From Wikipedia, the free encyclopedia
| Cardinal | One hundred [and] forty five |
| Ordinal | 145th |
| Factorization |  |
| Roman numeral | CXLV |
| Binary | 10010001 |
| Hexadecimal | 91 |
145 is the natural number following 144 and preceding 146.
[edit] In mathematics
Although composite, 145 is a pseudoprime.
Given 145, the Mertens function returns 0.
145 is a pentagonal number and a centered square number.
145 = 122 + 12 = 82 + 92. 145 is the fourth number that is the sum of two different pairs of squares. Also, 145 is the result of 34 + 43, making it a Leyland number.
145 = 1! + 4! + 5!. The only other numbers that have the property that they are the sum of the factorials of their digits are 1, 2 and 40585.
[edit] In other fields
For the year 145 AD, see 145.
