165669 has 20 divisors (see below), whose sum is σ = 268896. Its totient is φ = 90552.

The previous prime is 165667. The next prime is 165673. The reversal of 165669 is 966561.

It is not a de Polignac number, because 165669 - 2¹ = 165667 is a prime.

It is a super-2 number, since 2×165669² = 54892435122, which contains 22 as substring.

Its product of digits (9720) is a multiple of the sum of its prime factors (54).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165667) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7192 + ... + 7214.

2¹⁶⁵⁶⁶⁹ is an apocalyptic number.

It is an amenable number.

165669 is a deficient number, since it is larger than the sum of its proper divisors (103227).

165669 is an frugal number, since it uses more digits than its factorization.

165669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54 (or 33 counting only the distinct ones).

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

The square root of 165669 is about 407.0245692830. The cubic root of 165669 is about 54.9220935559.

The spelling of 165669 in words is "one hundred sixty-five thousand, six hundred sixty-nine".