821928 has 32 divisors (see below), whose sum is σ = 2145600. Its totient is φ = 261888.

The previous prime is 821911. The next prime is 821939. The reversal of 821928 is 829128.

It is a junction number, because it is equal to n+sod(n) for n = 821895 and 821904.

It is an unprimeable number.

821928 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 193 + ... + 1296.

It is an arithmetic number, because the mean of its divisors is an integer number (67050).

2⁸²¹⁹²⁸ is an apocalyptic number.

It is an amenable number.

821928 is an abundant number, since it is smaller than the sum of its proper divisors (1323672).

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

821928 is a wasteful number, since it uses less digits than its factorization.

821928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1521 (or 1517 counting only the distinct ones).

The product of its digits is 2304, while the sum is 30.

The square root of 821928 is about 906.6024487062. The cubic root of 821928 is about 93.6723160911.

The spelling of 821928 in words is "eight hundred twenty-one thousand, nine hundred twenty-eight".