9000 has 48 divisors (see below), whose sum is σ = 30420.
Its totient is φ = 2400.
The previous prime is 8999. The next prime is 9001. The reversal of 9000 is 9.
9000 = 103 + 113 + ... + 143.
It is a powerful number, because all its prime factors have an exponent greater than 1
and also an Achilles number because it is not a perfect power.
It is an interprime number because it is at equal distance from previous prime (8999) and next prime (9001).
It can be written as a sum of positive squares in 2 ways, for example, as 6084 + 2916 = 78^2 + 54^2
It is a Harshad number since it is a multiple of its sum of digits (9).
It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.
It is a plaindrome in base 14.
It is a nialpdrome in base 10.
It is a zygodrome in base 14.
It is not an unprimeable number, because it can be changed into a prime (9001) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1798 + ... + 1802.
29000 is an apocalyptic number.
9000 is a gapful number since it is divisible by the number (90) 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 9000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15210).
9000 is an abundant number, since it is smaller than the sum of its proper divisors (21420).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
9000 is a wasteful number, since it uses less digits than its factorization.
9000 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 27 (or 10 counting only the distinct ones).
The product of its (nonzero) digits is 9, while the sum is 9.
The square root of 9000 is about 94.8683298051.
The cubic root of 9000 is about 20.8008382305.
The spelling of 9000 in words is "nine thousand".