20868928 has 28 divisors (see below), whose sum is σ = 43850052. Its totient is φ = 9820160.

The previous prime is 20868907. The next prime is 20868929. The reversal of 20868928 is 82986802.

It can be written as a sum of positive squares in 2 ways, for example, as 16064064 + 4804864 = 4008^2 + 2192^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20868929) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 8503 + ... + 10678.

Almost surely, 2^20868928 is an apocalyptic number.

It is an amenable number.

20868928 is an abundant number, since it is smaller than the sum of its proper divisors (22981124).

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

20868928 is a wasteful number, since it uses less digits than its factorization.

20868928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19210 (or 19200 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 43.

The square root of 20868928 is about 4568.2521821808. The cubic root of 20868928 is about 275.3172229114.

The spelling of 20868928 in words is "twenty million, eight hundred sixty-eight thousand, nine hundred twenty-eight".