20838309 has 8 divisors (see below), whose sum is σ = 27806592. Its totient is φ = 13881120.

The previous prime is 20838281. The next prime is 20838317. The reversal of 20838309 is 90383802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20838309 - 2⁸ = 20838053 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20838309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20838329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3924 + ... + 7554.

It is an arithmetic number, because the mean of its divisors is an integer number (3475824).

Almost surely, 2^20838309 is an apocalyptic number.

It is an amenable number.

20838309 is a deficient number, since it is larger than the sum of its proper divisors (6968283).

20838309 is a wasteful number, since it uses less digits than its factorization.

20838309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5547.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 20838309 is about 4564.8996703104. The cubic root of 20838309 is about 275.1825080500.

Adding to 20838309 its reverse (90383802), we get a palindrome (111222111).

The spelling of 20838309 in words is "twenty million, eight hundred thirty-eight thousand, three hundred nine".