20885688 has 80 divisors (see below), whose sum is σ = 59154480. Its totient is φ = 6884352.

The previous prime is 20885663. The next prime is 20885701. The reversal of 20885688 is 88658802.

20885688 is a `hidden beast` number, since 2 + 0 + 88 + 568 + 8 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 108120 + ... + 108312.

It is an arithmetic number, because the mean of its divisors is an integer number (739431).

Almost surely, 2^20885688 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 20885688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29577240).

20885688 is an abundant number, since it is smaller than the sum of its proper divisors (38268792).

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

20885688 is a wasteful number, since it uses less digits than its factorization.

20885688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 45.

The square root of 20885688 is about 4570.0862136288. The cubic root of 20885688 is about 275.3909063311.

It can be divided in two parts, 2088 and 5688, that added together give a 5-th power (7776 = 6⁵).

The spelling of 20885688 in words is "twenty million, eight hundred eighty-five thousand, six hundred eighty-eight".