18780 has 24 divisors (see below), whose sum is σ = 52752. Its totient is φ = 4992.

The previous prime is 18773. The next prime is 18787. The reversal of 18780 is 8781.

18780 is nontrivially palindromic in base 14.

It is an interprime number because it is at equal distance from previous prime (18773) and next prime (18787).

It is a nialpdrome in base 12.

It is a self number, because there is not a number n which added to its sum of digits gives 18780.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18787) by changing a digit.

18780 is an untouchable number, because it is not equal to the sum of proper divisors of any 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, 97 + ... + 216.

It is an arithmetic number, because the mean of its divisors is an integer number (2198).

2¹⁸⁷⁸⁰ is an apocalyptic number.

18780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18780 is an abundant number, since it is smaller than the sum of its proper divisors (33972).

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 (26376).

18780 is a wasteful number, since it uses less digits than its factorization.

18780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 24.

The square root of 18780 is about 137.0401401050. The cubic root of 18780 is about 26.5806254605.

Subtracting from 18780 its reverse (8781), we obtain a palindrome (9999).

The spelling of 18780 in words is "eighteen thousand, seven hundred eighty".