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super Niven numbers
M.Saadatmanesh, R.E.Kennedy, and C.Cooper defined and studied the super Niven numbers (sN for brevity).

A number is called sN if it is divisible not only by the sum of its digits (like Harshad numbers) but also by the sum of any subset of its (nonzero) digits.

For example, the number 68040 is sN because it is divisible by 6, 8, 4, 6+8, 6+4, 4+8 and 6+4+8.

If  $n$  is sN, then clearly also  $10\cdot n$  is sN. The primitive sN numbers are those such that  $n/10$  is not sN.

It is easy to see that there are infinite primitive sN, because all the numbers of the form  $10^k+2$  are sN, being divisible by 1, 2, and 1 + 2 = 3.

The first super Niven numbers are 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 20, 24, 30, 36, 40, 48, 50, 60, 70, 80, 90, 100, 102, 110, 120, 140, 150, 200, 204, 210, 220, 240, 280, 300, 306, 330, 360, 400, 408, 420, 440, 480, 500 more terms

Super Niven numbers can also be... (you may click on names or numbers and on + to get more values)

ABA 24 50 200 + 45000000000 aban 10 12 20 + 48888000000 abundant 12 20 24 + 50000000 Achilles 200 500 800 + 45000000000 admirable 12 20 24 + 1000002 alternating 10 12 30 + 909090 amenable 12 20 24 + 1000000000 amicable 220 apocalyptic 220 540 660 + 30000 arithmetic 20 30 60 + 9909000 astonishing 204 betrothed 48 140 1050 binomial 10 20 36 + 20000100000 brilliant 10 c.nonagonal 10 2080 5050 + 5000050000 c.triangular 10 compositorial 24 congruent 20 24 30 + 9990000 constructible 10 12 20 + 4080 cube 1000 8000 1000000 + 8000000000 Cunningham 10 24 48 + 48400440000 Curzon 30 50 90 + 101000010 d-powerful 24 8200 42240 262200 decagonal 10 540 4000 69300 deficient 10 50 110 + 1000010 dig.balanced 10 12 50 + 180000000 double fact. 48 droll 240 800 Duffinian 36 50 100 + 9000000 eban 30 36 40 + 46006002000 economical 10 1000 2000 + 20000000 equidigital 10 1000 2000 + 15300000 eRAP 20 24 20220 esthetic 10 12 210 + 101010 Eulerian 120 evil 10 12 20 + 999099900 factorial 24 120 5040 40320 Friedman 12600 126000 153000 282240 frugal 10000 20000 40000 + 999000000 gapful 100 110 120 + 48888000000 Gilda 110 220 330 + 990 Giuga 30 happy 10 70 100 + 10000000 harmonic 140 30240 360360 Harshad 10 12 20 + 10000000000 heptagonal 540 351000 hexagonal 120 630 2016 + 2031120 highly composite 12 24 36 + 2205403200 hoax 660 2640 6060 + 96300000 iban 10 12 20 + 777000 idoneal 10 12 24 + 1320 inconsummate 630 840 2016 + 936000 interprime 12 30 50 + 99900000 Jordan-Polya 12 24 36 + 604800 junction 204 210 408 + 93000060 Kaprekar 5050 500500 50005000 5000050000 katadrome 10 20 30 + 840 Leyland 100 20000000000 lonely 120 Lynch-Bell 12 24 36 48 magic 500050 4000100 500000500 4000001000 magnanimous 12 20 30 + 110 metadrome 12 24 36 48 modest 100110 101010 200220 + 1400200200 nialpdrome 10 20 30 + 44444400000 nonagonal 24 204 4200 + 30060063000 nude 12 24 36 48 O'Halloran 12 20 36 + 660 oban 10 12 20 + 990 octagonal 40 280 408 + 606600 odious 50 70 100 + 1000000000 panconsummate 10 12 20 + 40 pandigital 120 210 990 + 360033300 partition 30 1002 pentagonal 12 70 210 + 8400 pernicious 10 12 20 + 9903600 Perrin 10 12 90 plaindrome 12 24 36 48 power 36 100 400 + 44100000000 powerful 36 100 200 + 45000000000 practical 12 20 24 + 10000000 prim.abundant 12 20 30 + 1000002 primorial 30 210 30030 pronic 12 20 30 + 40000200000 pseudoperfect 12 20 24 + 1000000 repunit 40 400 Ruth-Aaron 24 50 2020800 848000400 Saint-Exupery 60 480 2040 + 40260000000 self 20 110 400 + 888880800 semiprime 10 sliding 20 70 110 + 20000050000 sphenic 30 70 102 + 1000002 square 36 100 400 + 44100000000 straight-line 210 420 630 840 super-d 1050 3330 10500 + 9300060 superabundant 12 24 36 + 1102701600 tau 12 24 36 + 1000000000 taxicab 513000 4104000 111321000 + 4104000000 tetrahedral 10 20 120 + 7207200 triangular 10 36 120 + 20000100000 tribonacci 24 trimorphic 24 uban 10 12 20 + 48048000000 Ulam 36 48 102 + 9306000 undulating 1010 2020 3030 + 909090 unprimeable 200 204 510 + 10000000 untouchable 120 210 306 + 999000 vampire 15003000 1050021000 1500030000 wasteful 12 20 24 + 9990000 weird 70 Woodall 80 Zuckerman 12 24 36 Zumkeller 12 20 24 + 100000 zygodrome 1100 2200 3300 + 44880000000