166389 has 8 divisors (see below), whose sum is σ = 228000. Its totient is φ = 107856.

The previous prime is 166363. The next prime is 166393. The reversal of 166389 is 983661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 166389 - 2⁵ = 166357 is a prime.

It is a Curzon number.

166389 is a lucky number.

It is a plaindrome in base 14 and base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166319) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 639 + ... + 860.

It is an arithmetic number, because the mean of its divisors is an integer number (28500).

166389 is a Friedman number, since it can be written as 8+6+(9*6+1)^3, using all its digits and the basic arithmetic operations.

2¹⁶⁶³⁸⁹ is an apocalyptic number.

It is an amenable number.

166389 is a deficient number, since it is larger than the sum of its proper divisors (61611).

166389 is a wasteful number, since it uses less digits than its factorization.

166389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539.

The product of its digits is 7776, while the sum is 33.

The square root of 166389 is about 407.9080778803. The cubic root of 166389 is about 55.0015426565.

It can be divided in two parts, 166 and 389, that added together give a palindrome (555).

The spelling of 166389 in words is "one hundred sixty-six thousand, three hundred eighty-nine".