821618880 has 224 divisors, whose sum is σ = 2752856064. Its totient is φ = 207212544.

The previous prime is 821618851. The next prime is 821618921. The reversal of 821618880 is 88816128.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2804014 + ... + 2804306.

It is an arithmetic number, because the mean of its divisors is an integer number (12289536).

Almost surely, 2^821618880 is an apocalyptic number.

821618880 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 821618880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1376428032).

821618880 is an abundant number, since it is smaller than the sum of its proper divisors (1931237184).

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

821618880 is a wasteful number, since it uses less digits than its factorization.

821618880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 463 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 42.

The square root of 821618880 is about 28663.8950598135. The cubic root of 821618880 is about 936.6057150315.

The spelling of 821618880 in words is "eight hundred twenty-one million, six hundred eighteen thousand, eight hundred eighty".