18480 has 80 divisors (see below), whose sum is σ = 71424. Its totient is φ = 3840.
The previous prime is 18461. The next prime is 18481. The reversal of 18480 is 8481.
It is a tau number, because it is divible by the number of its divisors (80).
It is a super-3 number, since 3×184803 = 18933336576000, which contains 333 as substring.
It is a Harshad number since it is a multiple of its sum of digits (21).
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 (18481) by changing a digit.
18480 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1675 + ... + 1685.
218480 is an apocalyptic number.
18480 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 18480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35712).
18480 is an abundant number, since it is smaller than the sum of its proper divisors (52944).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
18480 is a wasteful number, since it uses less digits than its factorization.
18480 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 34 (or 28 counting only the distinct ones).
The product of its (nonzero) digits is 256, while the sum is 21.
The square root of 18480 is about 135.9411637437. The cubic root of 18480 is about 26.4383281657.
Subtracting from 18480 its reverse (8481), we obtain a palindrome (9999).
The spelling of 18480 in words is "eighteen thousand, four hundred eighty".
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