166656 has 72 divisors (see below), whose sum is σ = 523264. Its totient is φ = 46080.

The previous prime is 166643. The next prime is 166657. The reversal of 166656 is 656661.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 166656.

It is not an unprimeable number, because it can be changed into a prime (166657) by changing a digit.

166656 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5361 + ... + 5391.

2¹⁶⁶⁶⁵⁶ is an apocalyptic number.

166656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261632).

166656 is an abundant number, since it is smaller than the sum of its proper divisors (356608).

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

166656 is an equidigital number, since it uses as much as digits as its factorization.

166656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57 (or 43 counting only the distinct ones).

The product of its digits is 6480, while the sum is 30.

The square root of 166656 is about 408.2352263095. The cubic root of 166656 is about 55.0309467713.

The spelling of 166656 in words is "one hundred sixty-six thousand, six hundred fifty-six".