16866 has 12 divisors (see below), whose sum is σ = 36582. Its totient is φ = 5616.

The previous prime is 16843. The next prime is 16871. The reversal of 16866 is 66861.

It can be written as a sum of positive squares in only one way, i.e., 16641 + 225 = 129^2 + 15^2 .

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 an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 451 + ... + 486.

2¹⁶⁸⁶⁶ is an apocalyptic number.

16866 is an abundant number, since it is smaller than the sum of its proper divisors (19716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16866 is a wasteful number, since it uses less digits than its factorization.

16866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 945 (or 942 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 16866 is about 129.8691649315. The cubic root of 16866 is about 25.6450784534.

The spelling of 16866 in words is "sixteen thousand, eight hundred sixty-six".