821481363504 has 240 divisors, whose sum is σ = 2359368142560. Its totient is φ = 266720563200.

The previous prime is 821481363467. The next prime is 821481363509. The reversal of 821481363504 is 405363184128.

821481363504 is a `hidden beast` number, since 8 + 2 + 1 + 4 + 8 + 1 + 3 + 635 + 0 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 821481363504.

It is not an unprimeable number, because it can be changed into a prime (821481363509) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1171870354 + ... + 1171871054.

It is an arithmetic number, because the mean of its divisors is an integer number (9830700594).

Almost surely, 2^821481363504 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 821481363504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1179684071280).

821481363504 is an abundant number, since it is smaller than the sum of its proper divisors (1537886779056).

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

821481363504 is a wasteful number, since it uses less digits than its factorization.

821481363504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1660 (or 1651 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 821481363504 in words is "eight hundred twenty-one billion, four hundred eighty-one million, three hundred sixty-three thousand, five hundred four".