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18870880 = 255722983
BaseRepresentation
bin100011111111…
…1001001100000
31022111201222111
41013333021200
514312332010
61512245104
7316254100
oct107771140
938451874
1018870880
11a719a76
1263a0794
133ba9502
142713200
1519cb58a
hex11ff260

18870880 has 144 divisors (see below), whose sum is σ = 54295920. Its totient is φ = 6171648.

The previous prime is 18870871. The next prime is 18870883. The reversal of 18870880 is 8807881.

It is a super-3 number, since 3×188708803 (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18870883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 227319 + ... + 227401.

It is an arithmetic number, because the mean of its divisors is an integer number (377055).

Almost surely, 218870880 is an apocalyptic number.

18870880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18870880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27147960).

18870880 is an abundant number, since it is smaller than the sum of its proper divisors (35425040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18870880 is a wasteful number, since it uses less digits than its factorization.

18870880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 40.

The square root of 18870880 is about 4344.0626146500. The cubic root of 18870880 is about 266.2343272163.

The spelling of 18870880 in words is "eighteen million, eight hundred seventy thousand, eight hundred eighty".

Divisors: 1 2 4 5 7 8 10 14 16 20 28 29 32 35 40 49 56 58 70 80 83 98 112 116 140 145 160 166 196 203 224 232 245 280 290 332 392 406 415 464 490 560 580 581 664 784 812 830 928 980 1015 1120 1160 1162 1328 1421 1568 1624 1660 1960 2030 2320 2324 2407 2656 2842 2905 3248 3320 3920 4060 4067 4640 4648 4814 5684 5810 6496 6640 7105 7840 8120 8134 9296 9628 11368 11620 12035 13280 14210 16240 16268 16849 18592 19256 20335 22736 23240 24070 28420 32480 32536 33698 38512 40670 45472 46480 48140 56840 65072 67396 77024 81340 84245 92960 96280 113680 117943 130144 134792 162680 168490 192560 227360 235886 269584 325360 336980 385120 471772 539168 589715 650720 673960 943544 1179430 1347920 1887088 2358860 2695840 3774176 4717720 9435440 18870880