18680 has 16 divisors (see below), whose sum is σ = 42120. Its totient is φ = 7456.
The previous prime is 18679. The next prime is 18691. The reversal of 18680 is 8681.
It is a nialpdrome in base 12.
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 3 ways as a sum of consecutive naturals, for example, 194 + ... + 273.
218680 is an apocalyptic number.
18680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.
It is an amenable number.
18680 is an abundant number, since it is smaller than the sum of its proper divisors (23440).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21060).
18680 is a wasteful number, since it uses less digits than its factorization.
18680 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 478 (or 474 counting only the distinct ones).
The product of its (nonzero) digits is 384, while the sum is 23.
The square root of 18680 is about 136.6747965062. The cubic root of 18680 is about 26.5333625133.
Subtracting from 18680 its reverse (8681), we obtain a palindrome (9999).
The spelling of 18680 in words is "eighteen thousand, six hundred eighty".
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