6605 has 4 divisors (see below), whose sum is σ = 7932.
Its totient is φ = 5280.
The previous prime is 6599. The next prime is 6607. The reversal of 6605 is 5066.
It is a happy number.
It is a semiprime because it is the product of two primes.
It can be written as a sum of positive squares in 2 ways, for example, as 4489 + 2116 = 67^2 + 46^2
It is not a de Polignac number, because 6605 - 210 = 5581 is a prime.
It is a Duffinian number.
It is a plaindrome in base 14 and base 16.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (6607) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 656 + ... + 665.
It is an arithmetic number, because the mean of its divisors is an integer number (1983).
26605 is an apocalyptic number.
It is an amenable number.
6605 is a deficient number, since it is larger than the sum of its proper divisors (1327).
6605 is a wasteful number, since it uses less digits than its factorization.
6605 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1326.
The product of its (nonzero) digits is 180, while the sum is 17.
The square root of 6605 is about 81.2711510931.
The cubic root of 6605 is about 18.7625101698.
The spelling of 6605 in words is "six thousand, six hundred five".