821309168 has 40 divisors (see below), whose sum is σ = 1693820160. Its totient is φ = 384450560.

The previous prime is 821309149. The next prime is 821309189. The reversal of 821309168 is 861903128.

821309168 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 an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44048 + ... + 59856.

It is an arithmetic number, because the mean of its divisors is an integer number (42345504).

Almost surely, 2^821309168 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 821309168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (846910080).

821309168 is an abundant number, since it is smaller than the sum of its proper divisors (872510992).

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

821309168 is a wasteful number, since it uses less digits than its factorization.

821309168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16025 (or 16019 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 821309168 is about 28658.4920747760. The cubic root of 821309168 is about 936.4880146830.

The spelling of 821309168 in words is "eight hundred twenty-one million, three hundred nine thousand, one hundred sixty-eight".