163605 has 16 divisors (see below), whose sum is σ = 282240. Its totient is φ = 80448.

The previous prime is 163601. The next prime is 163613. The reversal of 163605 is 506361.

It is not a de Polignac number, because 163605 - 2² = 163601 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 225 + ... + 614.

It is an arithmetic number, because the mean of its divisors is an integer number (17640).

2¹⁶³⁶⁰⁵ is an apocalyptic number.

163605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

163605 is a deficient number, since it is larger than the sum of its proper divisors (118635).

163605 is a wasteful number, since it uses less digits than its factorization.

163605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860.

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 163605 is about 404.4811491281. The cubic root of 163605 is about 54.6930560341.

Adding to 163605 its reverse (506361), we get a palindrome (669966).

The spelling of 163605 in words is "one hundred sixty-three thousand, six hundred five".