20465728 has 28 divisors (see below), whose sum is σ = 41079420. Its totient is φ = 10115072.

The previous prime is 20465723. The next prime is 20465729. The reversal of 20465728 is 82756402.

It can be written as a sum of positive squares in 2 ways, for example, as 5161984 + 15303744 = 2272^2 + 3912^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20465693 and 20465702.

It is not an unprimeable number, because it can be changed into a prime (20465723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3900 + ... + 7492.

Almost surely, 2^20465728 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 20465728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20539710).

20465728 is an abundant number, since it is smaller than the sum of its proper divisors (20613692).

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

20465728 is an equidigital number, since it uses as much as digits as its factorization.

20465728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3694 (or 3684 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 20465728 is about 4523.9062766596. The cubic root of 20465728 is about 273.5325825934.

The spelling of 20465728 in words is "twenty million, four hundred sixty-five thousand, seven hundred twenty-eight".