20417856 has 112 divisors (see below), whose sum is σ = 59131200. Its totient is φ = 6193152.

The previous prime is 20417851. The next prime is 20417861. The reversal of 20417856 is 65871402.

It is an interprime number because it is at equal distance from previous prime (20417851) and next prime (20417861).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20417851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 105696 + ... + 105888.

Almost surely, 2^20417856 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 20417856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29565600).

20417856 is an abundant number, since it is smaller than the sum of its proper divisors (38713344).

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

20417856 is a wasteful number, since it uses less digits than its factorization.

20417856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 20417856 is about 4518.6121763214. The cubic root of 20417856 is about 273.3191399861.

The spelling of 20417856 in words is "twenty million, four hundred seventeen thousand, eight hundred fifty-six".