20208209 has 8 divisors (see below), whose sum is σ = 23123520. Its totient is φ = 17300016.

The previous prime is 20208163. The next prime is 20208217. The reversal of 20208209 is 90280202.

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 20208209 - 2⁸ = 20207953 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20208269) 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 in 7 ways as a sum of consecutive naturals, for example, 7667 + ... + 9959.

It is an arithmetic number, because the mean of its divisors is an integer number (2890440).

Almost surely, 2^20208209 is an apocalyptic number.

It is an amenable number.

20208209 is a deficient number, since it is larger than the sum of its proper divisors (2915311).

20208209 is a wasteful number, since it uses less digits than its factorization.

20208209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3559.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 20208209 is about 4495.3541573496. The cubic root of 20208209 is about 272.3804553775.

The spelling of 20208209 in words is "twenty million, two hundred eight thousand, two hundred nine".