20805033 has 4 divisors (see below), whose sum is σ = 27740048. Its totient is φ = 13870020.

The previous prime is 20805017. The next prime is 20805047. The reversal of 20805033 is 33050802.

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 not a de Polignac number, because 20805033 - 2⁴ = 20805017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20800033) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3467503 + ... + 3467508.

It is an arithmetic number, because the mean of its divisors is an integer number (6935012).

Almost surely, 2^20805033 is an apocalyptic number.

It is an amenable number.

20805033 is a deficient number, since it is larger than the sum of its proper divisors (6935015).

20805033 is an equidigital number, since it uses as much as digits as its factorization.

20805033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6935014.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 20805033 is about 4561.2534461483. The cubic root of 20805033 is about 275.0359534260.

Adding to 20805033 its reverse (33050802), we get a palindrome (53855835).

The spelling of 20805033 in words is "twenty million, eight hundred five thousand, thirty-three".