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18808 = 232351
BaseRepresentation
bin100100101111000
3221210121
410211320
51100213
6223024
7105556
oct44570
927717
1018808
1113149
12aa74
13873a
146bd6
15588d
hex4978

18808 has 8 divisors (see below), whose sum is σ = 35280. Its totient is φ = 9400.

The previous prime is 18803. The next prime is 18839. The reversal of 18808 is 80881.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a plaindrome in base 15.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18803) 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 as a sum of consecutive naturals, namely, 1168 + ... + 1183.

It is an arithmetic number, because the mean of its divisors is an integer number (4410).

218808 is an apocalyptic number.

It is an amenable number.

18808 is a deficient number, since it is larger than the sum of its proper divisors (16472).

18808 is a wasteful number, since it uses less digits than its factorization.

18808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2357 (or 2353 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 25.

The square root of 18808 is about 137.1422619035. The cubic root of 18808 is about 26.5938290093.

The spelling of 18808 in words is "eighteen thousand, eight hundred eight".

Divisors: 1 2 4 8 2351 4702 9404 18808