20345856 has 88 divisors (see below), whose sum is σ = 56005920. Its totient is φ = 6561792.

The previous prime is 20345839. The next prime is 20345863. The reversal of 20345856 is 65854302.

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, 113575 + ... + 113753.

Almost surely, 2^20345856 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 20345856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28002960).

20345856 is an abundant number, since it is smaller than the sum of its proper divisors (35660064).

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

20345856 is a wasteful number, since it uses less digits than its factorization.

20345856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239 (or 221 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 33.

The square root of 20345856 is about 4510.6380923324. The cubic root of 20345856 is about 272.9974908865.

The spelling of 20345856 in words is "twenty million, three hundred forty-five thousand, eight hundred fifty-six".