9009 has 24 divisors (see below), whose sum is σ = 17472.
Its totient is φ = 4320.
The previous prime is 9007. The next prime is 9011.
It can be divided in two parts, 900 and 9, that multiplied together give a square (8100 = 902).
9009 = 163 + 173.
9009 is nontrivially palindromic in base 2 and base 10.
It is an interprime number because it is at equal distance from previous prime (9007) and next prime (9011).
It is not a de Polignac number, because 9009 - 21 = 9007 is a prime.
9009 is a lucky number.
It is a junction number, because it is equal to n+sod(n) for n = 8982 and 9000.
It is not an unprimeable number, because it can be changed into a prime (9001) 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, 687 + ... + 699.
It is an arithmetic number, because the mean of its divisors is an integer number (728).
29009 is an apocalyptic number.
9009 is a gapful number since it is divisible by the number (99) formed by its first and last digit.
It is an amenable number.
9009 is a deficient number, since it is larger than the sum of its proper divisors (8463).
9009 is a wasteful number, since it uses less digits than its factorization.
9009 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 37 (or 34 counting only the distinct ones).
The product of its (nonzero) digits is 81, while the sum is 18.
The square root of 9009 is about 94.9157521173.
The cubic root of 9009 is about 20.8077695333.
The spelling of 9009 in words is "nine thousand, nine".