20805042 has 16 divisors (see below), whose sum is σ = 44057952. Its totient is φ = 6527040.

The previous prime is 20805017. The next prime is 20805047. The reversal of 20805042 is 24050802.

It is not an unprimeable number, because it can be changed into a prime (20805047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101884 + ... + 102087.

It is an arithmetic number, because the mean of its divisors is an integer number (2753622).

Almost surely, 2^20805042 is an apocalyptic number.

20805042 is an abundant number, since it is smaller than the sum of its proper divisors (23252910).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20805042 is a wasteful number, since it uses less digits than its factorization.

20805042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203993.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 20805042 is about 4561.2544327191. The cubic root of 20805042 is about 275.0359930850.

Adding to 20805042 its reverse (24050802), we get a palindrome (44855844).

The spelling of 20805042 in words is "twenty million, eight hundred five thousand, forty-two".