A natural number n is called strange if it satisfies the following two properties:
- The sum of its real divisors – other than the number itself – is greater than the number itself.
- It cannot be represented as the sum of some distinct divisors.
The first known strange numbers are
70,
836,
4030,
5830,
7192,
7912,
9272,
10430,
10570,
10792,
10990,
11410,
11690,
12110,
12530,
12670,
13370,
13510,
13790,
13930,
14770,
15610,
15890,
16030,
16310,
16730,
16870,
17272,
17570,
17990,
18410,
18830,
18970,
19390,
19670