20039209 has 8 divisors (see below), whose sum is σ = 21272328. Its totient is φ = 18812160.

The previous prime is 20039207. The next prime is 20039221. The reversal of 20039209 is 90293002.

It can be written as a sum of positive squares in 4 ways, for example, as 3229209 + 16810000 = 1797^2 + 4100^2 .

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 20039209 - 2¹ = 20039207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20039207) 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, 6559 + ... + 9115.

It is an arithmetic number, because the mean of its divisors is an integer number (2659041).

Almost surely, 2^20039209 is an apocalyptic number.

It is an amenable number.

20039209 is a deficient number, since it is larger than the sum of its proper divisors (1233119).

20039209 is a wasteful number, since it uses less digits than its factorization.

20039209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3035.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 20039209 is about 4476.5175080636. The cubic root of 20039209 is about 271.6190285362.

The spelling of 20039209 in words is "twenty million, thirty-nine thousand, two hundred nine".