16605 has 20 divisors (see below), whose sum is σ = 30492. Its totient is φ = 8640.

The previous prime is 16603. The next prime is 16607. The reversal of 16605 is 50661.

16605 is a `hidden beast` number, since 1 + 660 + 5 = 666.

16605 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (16603) and next prime (16607).

It can be written as a sum of positive squares in 2 ways, for example, as 2916 + 13689 = 54^2 + 117^2 .

It is not a de Polignac number, because 16605 - 2¹ = 16603 is a prime.

16605 is strictly pandigital in base 6.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16603) 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 in 19 ways as a sum of consecutive naturals, for example, 385 + ... + 425.

2¹⁶⁶⁰⁵ is an apocalyptic number.

16605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16605 is a deficient number, since it is larger than the sum of its proper divisors (13887).

16605 is an equidigital number, since it uses as much as digits as its factorization.

16605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58 (or 49 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 16605 is about 128.8603895695. The cubic root of 16605 is about 25.5121049794.

The spelling of 16605 in words is "sixteen thousand, six hundred five".