Abundant number

number for which the sum of its proper divisors is greater than the number itself

An abundant number is a number for which its sum of divisors, excluding itself, is greater than . 12 is an abundant number because . 18 is also an abundant number because . The series is in the Online Encyclopedia of Integer Sequences (Sloane) as A005101. 120 is considered a super abundant number since the sum of its divisors equals exactly twice the number. 945 is the first odd abundant number. The smallest odd abundant numbers that end in 1, 3, 7, and 9, are 81081, 153153, 207207, and 189189, respectively.

If a number is not abundant, it is called either deficient or perfect.

List of abundant numbers

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List of the first 120 abundant numbers:

12 18 20 24 30 36 40 42 48 54
56 60 66 70 72 78 80 84 88 90
96 100 102 104 108 112 114 120 126 132
138 140 144 150 156 160 162 168 174 176
180 186 192 196 198 200 204 208 210 216
220 222 224 228 234 240 246 252 258 260
264 270 272 276 280 282 288 294 300 304
306 308 312 318 320 324 330 336 340 342
348 350 352 354 360 364 366 368 372 378
380 384 390 392 396 400 402 408 414 416
420 426 432 438 440 444 448 450 456 460
462 464 468 474 480 486 490 492 498 500