821994339504 has 80 divisors (see below), whose sum is σ = 2309032823552. Its totient is φ = 250465768704.

The previous prime is 821994339499. The next prime is 821994339599. The reversal of 821994339504 is 405933499128.

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, 6330382 + ... + 6458925.

Almost surely, 2^821994339504 is an apocalyptic number.

It is an amenable number.

821994339504 is an abundant number, since it is smaller than the sum of its proper divisors (1487038484048).

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

821994339504 is a wasteful number, since it uses less digits than its factorization.

821994339504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12789434 (or 12789428 counting only the distinct ones).

The product of its (nonzero) digits is 8398080, while the sum is 57.

The spelling of 821994339504 in words is "eight hundred twenty-one billion, nine hundred ninety-four million, three hundred thirty-nine thousand, five hundred four".