16666687 has 4 divisors (see below), whose sum is σ = 17117176. Its totient is φ = 16216200.

The previous prime is 16666669. The next prime is 16666711. The reversal of 16666687 is 78666661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16666687 - 2¹⁵ = 16633919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16666607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225189 + ... + 225262.

It is an arithmetic number, because the mean of its divisors is an integer number (4279294).

Almost surely, 2^16666687 is an apocalyptic number.

16666687 is a deficient number, since it is larger than the sum of its proper divisors (450489).

16666687 is an equidigital number, since it uses as much as digits as its factorization.

16666687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450488.

The product of its digits is 435456, while the sum is 46.

The square root of 16666687 is about 4082.4853949524. The cubic root of 16666687 is about 255.4365813420.

It can be divided in two parts, 166666 and 87, that added together give a triangular number (166753 = T₅₇₇).

The spelling of 16666687 in words is "sixteen million, six hundred sixty-six thousand, six hundred eighty-seven".