20205856 has 48 divisors (see below), whose sum is σ = 43817760. Its totient is φ = 9095680.

The previous prime is 20205847. The next prime is 20205859. The reversal of 20205856 is 65850202.

20205856 = 314² + 315² + ... + 450².

It is not an unprimeable number, because it can be changed into a prime (20205859) 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, 48015 + ... + 48433.

It is an arithmetic number, because the mean of its divisors is an integer number (912870).

Almost surely, 2^20205856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20205856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21908880).

20205856 is an abundant number, since it is smaller than the sum of its proper divisors (23611904).

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

20205856 is a wasteful number, since it uses less digits than its factorization.

20205856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577 (or 569 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 20205856 is about 4495.0924350896. The cubic root of 20205856 is about 272.3698831708.

The spelling of 20205856 in words is "twenty million, two hundred five thousand, eight hundred fifty-six".