821584644468 has 48 divisors (see below), whose sum is σ = 2190983208960. Its totient is φ = 234728738784.

The previous prime is 821584644443. The next prime is 821584644479. The reversal of 821584644468 is 864446485128.

821584644468 is digitally balanced in base 2 and base 4, because in such bases 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 15 ways as a sum of consecutive naturals, for example, 1973905 + ... + 2353607.

It is an arithmetic number, because the mean of its divisors is an integer number (45645483520).

Almost surely, 2^821584644468 is an apocalyptic number.

It is an amenable number.

821584644468 is an abundant number, since it is smaller than the sum of its proper divisors (1369398564492).

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

821584644468 is a wasteful number, since it uses less digits than its factorization.

821584644468 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405476 (or 405474 counting only the distinct ones).

The product of its digits is 47185920, while the sum is 60.

The spelling of 821584644468 in words is "eight hundred twenty-one billion, five hundred eighty-four million, six hundred forty-four thousand, four hundred sixty-eight".