20393728 has 72 divisors (see below), whose sum is σ = 43782480. Its totient is φ = 9461760.

The previous prime is 20393717. The next prime is 20393729. The reversal of 20393728 is 82739302.

It is a junction number, because it is equal to n+sod(n) for n = 20393693 and 20393702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20393729) 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 7 ways as a sum of consecutive naturals, for example, 304351 + ... + 304417.

It is an arithmetic number, because the mean of its divisors is an integer number (608090).

Almost surely, 2^20393728 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 20393728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21891240).

20393728 is an abundant number, since it is smaller than the sum of its proper divisors (23388752).

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

20393728 is an equidigital number, since it uses as much as digits as its factorization.

20393728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 20393728 is about 4515.9415408085. The cubic root of 20393728 is about 273.2114361611.

The spelling of 20393728 in words is "twenty million, three hundred ninety-three thousand, seven hundred twenty-eight".