163566 has 32 divisors (see below), whose sum is σ = 393120. Its totient is φ = 50112.

The previous prime is 163561. The next prime is 163567. The reversal of 163566 is 665361.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 586 + ... + 818.

It is an arithmetic number, because the mean of its divisors is an integer number (12285).

2¹⁶³⁵⁶⁶ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 163566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (196560).

163566 is an abundant number, since it is smaller than the sum of its proper divisors (229554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

163566 is a wasteful number, since it uses less digits than its factorization.

163566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 251 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 163566 is about 404.4329363442. The cubic root of 163566 is about 54.6887097964.

It can be divided in two parts, 163 and 566, that added together give a 6-th power (729 = 3⁶).

The spelling of 163566 in words is "one hundred sixty-three thousand, five hundred sixty-six".