16666987 has 8 divisors (see below), whose sum is σ = 17912016. Its totient is φ = 15451392.

The previous prime is 16666961. The next prime is 16666997. The reversal of 16666987 is 78966661.

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

It is a cyclic number.

It is not a de Polignac number, because 16666987 - 2¹¹ = 16664939 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16666987.

It is not an unprimeable number, because it can be changed into a prime (16666907) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6178 + ... + 8455.

It is an arithmetic number, because the mean of its divisors is an integer number (2239002).

Almost surely, 2^16666987 is an apocalyptic number.

16666987 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

16666987 is a deficient number, since it is larger than the sum of its proper divisors (1245029).

16666987 is a wasteful number, since it uses less digits than its factorization.

16666987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14717.

The product of its digits is 653184, while the sum is 49.

The square root of 16666987 is about 4082.5221371108. The cubic root of 16666987 is about 255.4381139504.

The spelling of 16666987 in words is "sixteen million, six hundred sixty-six thousand, nine hundred eighty-seven".