16387866 has 64 divisors (see below), whose sum is σ = 40642560. Its totient is φ = 4852080.

The previous prime is 16387853. The next prime is 16387867. The reversal of 16387866 is 66878361.

16387866 is a `hidden beast` number, since 1 + 638 + 7 + 8 + 6 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (16387867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27625 + ... + 28211.

It is an arithmetic number, because the mean of its divisors is an integer number (635040).

Almost surely, 2^16387866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16387866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20321280).

16387866 is an abundant number, since it is smaller than the sum of its proper divisors (24254694).

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

16387866 is a wasteful number, since it uses less digits than its factorization.

16387866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 656 (or 650 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 16387866 is about 4048.1929301850. The cubic root of 16387866 is about 254.0041436074.

The spelling of 16387866 in words is "sixteen million, three hundred eighty-seven thousand, eight hundred sixty-six".