1921020928 has 22 divisors (see below), whose sum is σ = 3840167906. Its totient is φ = 960509952.

The previous prime is 1921020919. The next prime is 1921020931. The reversal of 1921020928 is 8290201291.

It can be written as a sum of positive squares in only one way, i.e., 965469184 + 955551744 = 31072^2 + 30912^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1921020893 and 1921020902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 936975 + ... + 939022.

Almost surely, 2^1921020928 is an apocalyptic number.

It is an amenable number.

1921020928 is a deficient number, since it is larger than the sum of its proper divisors (1919146978).

1921020928 is an equidigital number, since it uses as much as digits as its factorization.

1921020928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1876017 (or 1875999 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 1921020928 is about 43829.4527458420. The cubic root of 1921020928 is about 1243.1132592266.

The spelling of 1921020928 in words is "one billion, nine hundred twenty-one million, twenty thousand, nine hundred twenty-eight".