166666 has 8 divisors (see below), whose sum is σ = 252000. Its totient is φ = 82668.

The previous prime is 166657. The next prime is 166667. The reversal of 166666 is 666661.

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

166666 is a modest number, since divided by 666 gives 166 as remainder.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (166667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85 + ... + 583.

It is an arithmetic number, because the mean of its divisors is an integer number (31500).

2¹⁶⁶⁶⁶⁶ is an apocalyptic number.

166666 is a deficient number, since it is larger than the sum of its proper divisors (85334).

166666 is a wasteful number, since it uses less digits than its factorization.

166666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668.

The product of its digits is 7776, while the sum is 31.

The square root of 166666 is about 408.2474739665. The cubic root of 166666 is about 55.0320474387.

The spelling of 166666 in words is "one hundred sixty-six thousand, six hundred sixty-six".