16671209 has 2 divisors, whose sum is σ = 16671210. Its totient is φ = 16671208.

The previous prime is 16671199. The next prime is 16671233. The reversal of 16671209 is 90217661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13875625 + 2795584 = 3725^2 + 1672^2 .

It is a cyclic number.

It is not a de Polignac number, because 16671209 - 2¹² = 16667113 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16671269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8335604 + 8335605.

It is an arithmetic number, because the mean of its divisors is an integer number (8335605).

Almost surely, 2^16671209 is an apocalyptic number.

It is an amenable number.

16671209 is a deficient number, since it is larger than the sum of its proper divisors (1).

16671209 is an equidigital number, since it uses as much as digits as its factorization.

16671209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 16671209 is about 4083.0391866844. The cubic root of 16671209 is about 255.4596809092.

The spelling of 16671209 in words is "sixteen million, six hundred seventy-one thousand, two hundred nine".