165966 has 16 divisors (see below), whose sum is σ = 336000. Its totient is φ = 54648.

The previous prime is 165961. The next prime is 165983. The reversal of 165966 is 669561.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165961) by changing a digit.

165966 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 (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 735 + ... + 933.

It is an arithmetic number, because the mean of its divisors is an integer number (21000).

2¹⁶⁵⁹⁶⁶ is an apocalyptic number.

165966 is an abundant number, since it is smaller than the sum of its proper divisors (170034).

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

165966 is a wasteful number, since it uses less digits than its factorization.

165966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343.

The product of its digits is 9720, while the sum is 33.

The square root of 165966 is about 407.3892487536. The cubic root of 165966 is about 54.9548941480.

The spelling of 165966 in words is "one hundred sixty-five thousand, nine hundred sixty-six".