16660566 has 64 divisors (see below), whose sum is σ = 40501440. Its totient is φ = 5108832.

The previous prime is 16660543. The next prime is 16660577. The reversal of 16660566 is 66506661.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 16660566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56716 + ... + 57008.

It is an arithmetic number, because the mean of its divisors is an integer number (632835).

Almost surely, 2^16660566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16660566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20250720).

16660566 is an abundant number, since it is smaller than the sum of its proper divisors (23840874).

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

16660566 is an equidigital number, since it uses as much as digits as its factorization.

16660566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329 (or 311 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 16660566 is about 4081.7356602308. The cubic root of 16660566 is about 255.4053070049.

The spelling of 16660566 in words is "sixteen million, six hundred sixty thousand, five hundred sixty-six".