20833809 has 4 divisors (see below), whose sum is σ = 27778416. Its totient is φ = 13889204.

The previous prime is 20833807. The next prime is 20833811. The reversal of 20833809 is 90833802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (20833807) and next prime (20833811).

It is a cyclic number.

It is not a de Polignac number, because 20833809 - 2¹ = 20833807 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20833809.

It is not an unprimeable number, because it can be changed into a prime (20833807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3472299 + ... + 3472304.

It is an arithmetic number, because the mean of its divisors is an integer number (6944604).

Almost surely, 2^20833809 is an apocalyptic number.

It is an amenable number.

20833809 is a deficient number, since it is larger than the sum of its proper divisors (6944607).

20833809 is an equidigital number, since it uses as much as digits as its factorization.

20833809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6944606.

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

The square root of 20833809 is about 4564.4067522516. The cubic root of 20833809 is about 275.1626982143.

The spelling of 20833809 in words is "twenty million, eight hundred thirty-three thousand, eight hundred nine".