164565 has 32 divisors (see below), whose sum is σ = 311040. Its totient is φ = 82368.

The previous prime is 164531. The next prime is 164569. The reversal of 164565 is 565461.

It is a happy number.

It is not a de Polignac number, because 164565 - 2⁸ = 164309 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

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

Its product of digits (3600) is a multiple of the sum of its prime factors (90).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164569) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3079 + ... + 3131.

It is an arithmetic number, because the mean of its divisors is an integer number (9720).

2¹⁶⁴⁵⁶⁵ is an apocalyptic number.

164565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

164565 is a deficient number, since it is larger than the sum of its proper divisors (146475).

164565 is a wasteful number, since it uses less digits than its factorization.

164565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 84 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 164565 is about 405.6661188712. Note that the first 3 decimals coincide. The cubic root of 164565 is about 54.7998232896.

It can be divided in two parts, 16456 and 5, that added together give a palindrome (16461).

The spelling of 164565 in words is "one hundred sixty-four thousand, five hundred sixty-five".