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28320 = 253559
BaseRepresentation
bin110111010100000
31102211220
412322200
51401240
6335040
7145365
oct67240
942756
1028320
111a306
1214480
13cb76
14a46c
1585d0
hex6ea0

28320 has 48 divisors (see below), whose sum is σ = 90720. Its totient is φ = 7424.

The previous prime is 28319. The next prime is 28349. The reversal of 28320 is 2382.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a nialpdrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 28320.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 451 + ... + 509.

It is an arithmetic number, because the mean of its divisors is an integer number (1890).

228320 is an apocalyptic number.

28320 is a gapful number since it is divisible by the number (20) 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 28320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45360).

28320 is an abundant number, since it is smaller than the sum of its proper divisors (62400).

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

28320 is a wasteful number, since it uses less digits than its factorization.

28320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 28320 is about 168.2854717437. The cubic root of 28320 is about 30.4811313914.

Subtracting from 28320 its product of nonzero digits (96), we obtain a square (28224 = 1682).

It can be divided in two parts, 283 and 20, that added together give a palindrome (303).

The spelling of 28320 in words is "twenty-eight thousand, three hundred twenty".

Divisors: 1 2 3 4 5 6 8 10 12 15 16 20 24 30 32 40 48 59 60 80 96 118 120 160 177 236 240 295 354 472 480 590 708 885 944 1180 1416 1770 1888 2360 2832 3540 4720 5664 7080 9440 14160 28320