821899648 has 32 divisors (see below), whose sum is σ = 1681641360. Its totient is φ = 399840768.

The previous prime is 821899619. The next prime is 821899667. The reversal of 821899648 is 846998128.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 82036 + ... + 91507.

Almost surely, 2^821899648 is an apocalyptic number.

It is an amenable number.

821899648 is an abundant number, since it is smaller than the sum of its proper divisors (859741712).

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

821899648 is a wasteful number, since it uses less digits than its factorization.

821899648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173594 (or 173582 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 55.

The square root of 821899648 is about 28668.7922312748. The cubic root of 821899648 is about 936.7123901867.

The spelling of 821899648 in words is "eight hundred twenty-one million, eight hundred ninety-nine thousand, six hundred forty-eight".