1021728 has 48 divisors (see below), whose sum is σ = 2782080. Its totient is φ = 327936.

The previous prime is 1021711. The next prime is 1021747. The reversal of 1021728 is 8271201.

1021728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (48).

It is a nialpdrome in base 16.

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, 2601 + ... + 2967.

It is an arithmetic number, because the mean of its divisors is an integer number (57960).

2^1021728 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 1021728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1391040).

1021728 is an abundant number, since it is smaller than the sum of its proper divisors (1760352).

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

1021728 is a wasteful number, since it uses less digits than its factorization.

1021728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409 (or 401 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 21.

The square root of 1021728 is about 1010.8056192958. The cubic root of 1021728 is about 100.7190834623.

Adding to 1021728 its reverse (8271201), we get a palindrome (9292929).

It can be divided in two parts, 102 and 1728, that added together give a triangular number (1830 = T₆₀).

The spelling of 1021728 in words is "one million, twenty-one thousand, seven hundred twenty-eight".