39985209 has 24 divisors (see below), whose sum is σ = 64550304. Its totient is φ = 23640000.

The previous prime is 39985189. The next prime is 39985289. The reversal of 39985209 is 90258993.

39985209 is a `hidden beast` number, since 39 + 98 + 520 + 9 = 666.

It is not a de Polignac number, because 39985209 - 2⁷ = 39985081 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (39985289) 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, 867 + ... + 8984.

It is an arithmetic number, because the mean of its divisors is an integer number (2689596).

Almost surely, 2^39985209 is an apocalyptic number.

It is an amenable number.

39985209 is a deficient number, since it is larger than the sum of its proper divisors (24565095).

39985209 is a wasteful number, since it uses less digits than its factorization.

39985209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9909 (or 9906 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 45.

The square root of 39985209 is about 6323.3858809976. The cubic root of 39985209 is about 341.9530303814.

The spelling of 39985209 in words is "thirty-nine million, nine hundred eighty-five thousand, two hundred nine".