20305806 has 16 divisors (see below), whose sum is σ = 41922048. Its totient is φ = 6550200.

The previous prime is 20305799. The next prime is 20305811. The reversal of 20305806 is 60850302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54400 + ... + 54771.

It is an arithmetic number, because the mean of its divisors is an integer number (2620128).

Almost surely, 2^20305806 is an apocalyptic number.

20305806 is an abundant number, since it is smaller than the sum of its proper divisors (21616242).

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

20305806 is a wasteful number, since it uses less digits than its factorization.

20305806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109207.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 20305806 is about 4506.1964005134. The cubic root of 20305806 is about 272.8182450252.

The spelling of 20305806 in words is "twenty million, three hundred five thousand, eight hundred six".