16887209 has 2 divisors, whose sum is σ = 16887210. Its totient is φ = 16887208.

The previous prime is 16887197. The next prime is 16887217. The reversal of 16887209 is 90278861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10272025 + 6615184 = 3205^2 + 2572^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16887209 is a prime.

It is not a weakly prime, because it can be changed into another prime (16887509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8443604 + 8443605.

It is an arithmetic number, because the mean of its divisors is an integer number (8443605).

Almost surely, 2^16887209 is an apocalyptic number.

It is an amenable number.

16887209 is a deficient number, since it is larger than the sum of its proper divisors (1).

16887209 is an equidigital number, since it uses as much as digits as its factorization.

16887209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 16887209 is about 4109.4049447578. The cubic root of 16887209 is about 256.5582351527.

The spelling of 16887209 in words is "sixteen million, eight hundred eighty-seven thousand, two hundred nine".