821013504 has 176 divisors, whose sum is σ = 2358144000. Its totient is φ = 253034496.

The previous prime is 821013499. The next prime is 821013527. The reversal of 821013504 is 405310128.

It is a Harshad number since it is a multiple of its sum of digits (24).

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 15 ways as a sum of consecutive naturals, for example, 4125597 + ... + 4125795.

Almost surely, 2^821013504 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 821013504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1179072000).

821013504 is an abundant number, since it is smaller than the sum of its proper divisors (1537130496).

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

821013504 is a wasteful number, since it uses less digits than its factorization.

821013504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318 (or 300 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 821013504 is about 28653.3332092446. Note that the first 3 decimals coincide. The cubic root of 821013504 is about 936.3756254086.

The spelling of 821013504 in words is "eight hundred twenty-one million, thirteen thousand, five hundred four".