20209843 has 8 divisors (see below), whose sum is σ = 20815200. Its totient is φ = 19609920.

The previous prime is 20209841. The next prime is 20209883. The reversal of 20209843 is 34890202.

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 20209843 - 2¹ = 20209841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20209841) 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, 6921 + ... + 9397.

It is an arithmetic number, because the mean of its divisors is an integer number (2601900).

Almost surely, 2^20209843 is an apocalyptic number.

20209843 is a deficient number, since it is larger than the sum of its proper divisors (605357).

20209843 is a wasteful number, since it uses less digits than its factorization.

20209843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2717.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 20209843 is about 4495.5358968648. The cubic root of 20209843 is about 272.3877965801.

The spelling of 20209843 in words is "twenty million, two hundred nine thousand, eight hundred forty-three".