20838743 has 4 divisors (see below), whose sum is σ = 20884800. Its totient is φ = 20792688.

The previous prime is 20838721. The next prime is 20838751. The reversal of 20838743 is 34783802.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20838743 - 2¹² = 20834647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20838793) 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 3 ways as a sum of consecutive naturals, for example, 22343 + ... + 23256.

It is an arithmetic number, because the mean of its divisors is an integer number (5221200).

Almost surely, 2^20838743 is an apocalyptic number.

20838743 is a deficient number, since it is larger than the sum of its proper divisors (46057).

20838743 is an equidigital number, since it uses as much as digits as its factorization.

20838743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46056.

The product of its (nonzero) digits is 32256, while the sum is 35.

The square root of 20838743 is about 4564.9472067046. The cubic root of 20838743 is about 275.1844184478.

The spelling of 20838743 in words is "twenty million, eight hundred thirty-eight thousand, seven hundred forty-three".