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128520 = 23335717
BaseRepresentation
bin11111011000001000
320112022000
4133120020
513103040
62431000
71043460
oct373010
9215260
10128520
1188617
1262460
1346662
1434ba0
1528130
hex1f608

128520 has 128 divisors (see below), whose sum is σ = 518400. Its totient is φ = 27648.

The previous prime is 128519. The next prime is 128521. The reversal of 128520 is 25821.

It is an interprime number because it is at equal distance from previous prime (128519) and next prime (128521).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 128493 and 128502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128521) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7552 + ... + 7568.

It is an arithmetic number, because the mean of its divisors is an integer number (4050).

2128520 is an apocalyptic number.

128520 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 128520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (259200).

128520 is an abundant number, since it is smaller than the sum of its proper divisors (389880).

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

128520 is a wasteful number, since it uses less digits than its factorization.

128520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44 (or 34 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 128520 is about 358.4968619110. The cubic root of 128520 is about 50.4649955113.

128520 divided by its sum of digits (18) gives a triangular number (7140 = T119).

The spelling of 128520 in words is "one hundred twenty-eight thousand, five hundred twenty".

Divisors: 1 2 3 4 5 6 7 8 9 10 12 14 15 17 18 20 21 24 27 28 30 34 35 36 40 42 45 51 54 56 60 63 68 70 72 84 85 90 102 105 108 119 120 126 135 136 140 153 168 170 180 189 204 210 216 238 252 255 270 280 306 315 340 357 360 378 408 420 459 476 504 510 540 595 612 630 680 714 756 765 840 918 945 952 1020 1071 1080 1190 1224 1260 1428 1512 1530 1785 1836 1890 2040 2142 2295 2380 2520 2856 3060 3213 3570 3672 3780 4284 4590 4760 5355 6120 6426 7140 7560 8568 9180 10710 12852 14280 16065 18360 21420 25704 32130 42840 64260 128520