209086009 has 24 divisors (see below), whose sum is σ = 245354400. Its totient is φ = 176647680.

The previous prime is 209085997. The next prime is 209086021. The reversal of 209086009 is 900680902.

It is an interprime number because it is at equal distance from previous prime (209085997) and next prime (209086021).

It is not a de Polignac number, because 209086009 - 2⁹ = 209085497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209086039) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 282562 + ... + 283300.

It is an arithmetic number, because the mean of its divisors is an integer number (10223100).

Almost surely, 2^209086009 is an apocalyptic number.

It is an amenable number.

209086009 is a deficient number, since it is larger than the sum of its proper divisors (36268391).

209086009 is a wasteful number, since it uses less digits than its factorization.

209086009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 873 (or 856 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 209086009 is about 14459.8066722899. The cubic root of 209086009 is about 593.5286092575.

The spelling of 209086009 in words is "two hundred nine million, eighty-six thousand, nine".