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10009 is a prime number

10009 has 2 divisors, whose sum is σ = 10010. Its totient is φ = 10008.

The previous prime is 10007. The next prime is 10037. The reversal of 10009 is 90001.

It is a happy number.

10009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10000 + 9 = 100^2 + 3^2 .

It is an emirp because it is prime and its reverse (90001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10009 - 21 = 10007 is a prime.

Together with 10007, it forms a pair of twin primes.

10009 is a modest number, since divided by 9 gives 1 as remainder.

10009 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 9977 and 10004.

It is not a weakly prime, because it can be changed into another prime (10007) by changing a digit.

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 as a sum of consecutive naturals, namely, 5004 + 5005.

It is an arithmetic number, because the mean of its divisors is an integer number (5005).

210009 is an apocalyptic number.

It is an amenable number.

10009 is a deficient number, since it is larger than the sum of its proper divisors (1).

10009 is an equidigital number, since it uses as much as digits as its factorization.

10009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9, while the sum is 10.

The square root of 10009 is about 100.0449898796. The cubic root of 10009 is about 21.5508082664.

Subtracting from 10009 its sum of digits (10), we obtain a palindrome (9999).

The spelling of 10009 in words is "ten thousand, nine".