1028921784 has 64 divisors (see below), whose sum is σ = 2840019840. Its totient is φ = 308031360.

The previous prime is 1028921783. The next prime is 1028921797. The reversal of 1028921784 is 4871298201.

1028921784 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1028921783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1567 + ... + 45390.

It is an arithmetic number, because the mean of its divisors is an integer number (44375310).

Almost surely, 2^1028921784 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 1028921784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1420009920).

1028921784 is an abundant number, since it is smaller than the sum of its proper divisors (1811098056).

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

1028921784 is a wasteful number, since it uses less digits than its factorization.

1028921784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47060 (or 47056 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 42.

The square root of 1028921784 is about 32076.8106893438. The cubic root of 1028921784 is about 1009.5491187502.

The spelling of 1028921784 in words is "one billion, twenty-eight million, nine hundred twenty-one thousand, seven hundred eighty-four".