166623 has 4 divisors (see below), whose sum is σ = 222168. Its totient is φ = 111080.

The previous prime is 166619. The next prime is 166627. The reversal of 166623 is 326661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 326661 = 3 ⋅108887.

It is an interprime number because it is at equal distance from previous prime (166619) and next prime (166627).

It is a cyclic number.

It is not a de Polignac number, because 166623 - 2² = 166619 is a prime.

It is a D-number.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 166593 and 166602.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 166623.

It is not an unprimeable number, because it can be changed into a prime (166627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27768 + ... + 27773.

It is an arithmetic number, because the mean of its divisors is an integer number (55542).

2¹⁶⁶⁶²³ is an apocalyptic number.

166623 is a deficient number, since it is larger than the sum of its proper divisors (55545).

166623 is an equidigital number, since it uses as much as digits as its factorization.

166623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55544.

The product of its digits is 1296, while the sum is 24.

The square root of 166623 is about 408.1948064344. The cubic root of 166623 is about 55.0273142566.

The spelling of 166623 in words is "one hundred sixty-six thousand, six hundred twenty-three".