8505 has 24 divisors (see below), whose sum is σ = 17472.
Its totient is φ = 3888.
The previous prime is 8501. The next prime is 8513. The reversal of 8505 is 5058.
It is not a de Polignac number, because 8505 - 22 = 8501 is a prime.
It is an alternating number because its digits alternate between even and odd.
It is a Curzon number.
It is a nialpdrome in base 11.
It is not an unprimeable number, because it can be changed into a prime (8501) by changing a digit.
It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1212 + ... + 1218.
It is an arithmetic number, because the mean of its divisors is an integer number (728).
28505 is an apocalyptic number.
It is an amenable number.
8505 is an abundant number, since it is smaller than the sum of its proper divisors (8967).
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 (8736).
8505 is an equidigital number, since it uses as much as digits as its factorization.
8505 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 27 (or 15 counting only the distinct ones).
The product of its (nonzero) digits is 200, while the sum is 18.
The square root of 8505 is about 92.2225568936.
Note that the first 3 decimals coincide.
The cubic root of 8505 is about 20.4122763479.
The spelling of 8505 in words is "eight thousand, five hundred five".