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20384 = 257213
BaseRepresentation
bin100111110100000
31000221222
410332200
51123014
6234212
7113300
oct47640
930858
1020384
1114351
12b968
139380
147600
15608e
hex4fa0

20384 has 36 divisors (see below), whose sum is σ = 50274. Its totient is φ = 8064.

The previous prime is 20369. The next prime is 20389. The reversal of 20384 is 48302.

20384 = 113 + 123 + ... + 173.

It can be written as a sum of positive squares in only one way, i.e., 19600 + 784 = 140^2 + 28^2 .

It is a nialpdrome in base 14.

It is a zygodrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (20389) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 1562 + ... + 1574.

220384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25137).

20384 is an abundant number, since it is smaller than the sum of its proper divisors (29890).

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

20384 is a wasteful number, since it uses less digits than its factorization.

20384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37 (or 22 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 20384 is about 142.7725463806. The cubic root of 20384 is about 27.3167987777.

Multiplying 20384 by its sum of digits (17), we get a triangular number (346528 = T832).

Adding to 20384 its reverse (48302), we get a palindrome (68686).

It can be divided in two parts, 20 and 384, that added together give a palindrome (404).

The spelling of 20384 in words is "twenty thousand, three hundred eighty-four".