821696384 has 16 divisors (see below), whose sum is σ = 1636973520. Its totient is φ = 410848128.

The previous prime is 821696357. The next prime is 821696387. The reversal of 821696384 is 483696128.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821696387) by changing a digit.

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 as a sum of consecutive naturals, namely, 3209624 + ... + 3209879.

It is an arithmetic number, because the mean of its divisors is an integer number (102310845).

Almost surely, 2^821696384 is an apocalyptic number.

It is an amenable number.

821696384 is a deficient number, since it is larger than the sum of its proper divisors (815277136).

821696384 is an equidigital number, since it uses as much as digits as its factorization.

821696384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6419517 (or 6419505 counting only the distinct ones).

The product of its digits is 497664, while the sum is 47.

The square root of 821696384 is about 28665.2469725973. The cubic root of 821696384 is about 936.6351643738.

The spelling of 821696384 in words is "eight hundred twenty-one million, six hundred ninety-six thousand, three hundred eighty-four".