821919120 has 320 divisors, whose sum is σ = 2927812608. Its totient is φ = 190502400.

The previous prime is 821919101. The next prime is 821919167. The reversal of 821919120 is 21919128.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9902599 + ... + 9902681.

Almost surely, 2^821919120 is an apocalyptic number.

821919120 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 821919120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1463906304).

821919120 is an abundant number, since it is smaller than the sum of its proper divisors (2105893488).

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

821919120 is a wasteful number, since it uses less digits than its factorization.

821919120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163 (or 135 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 33.

The square root of 821919120 is about 28669.1318319896. The cubic root of 821919120 is about 936.7197874887.

The spelling of 821919120 in words is "eight hundred twenty-one million, nine hundred nineteen thousand, one hundred twenty".