166889 has 4 divisors (see below), whose sum is σ = 176724. Its totient is φ = 157056.

The previous prime is 166871. The next prime is 166909. The reversal of 166889 is 988661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 153664 + 13225 = 392^2 + 115^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166889 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 10 and base 15.

It is not an unprimeable number, because it can be changed into a prime (166849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4892 + ... + 4925.

It is an arithmetic number, because the mean of its divisors is an integer number (44181).

2¹⁶⁶⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

166889 is a deficient number, since it is larger than the sum of its proper divisors (9835).

166889 is an equidigital number, since it uses as much as digits as its factorization.

166889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9834.

The product of its digits is 20736, while the sum is 38.

The square root of 166889 is about 408.5205013215. The cubic root of 166889 is about 55.0565808913.

It can be divided in two parts, 16 and 6889, that multiplied together give a square (110224 = 332²).

The spelling of 166889 in words is "one hundred sixty-six thousand, eight hundred eighty-nine".