16821255828 has 48 divisors (see below), whose sum is σ = 43251809216. Its totient is φ = 5055402240.

The previous prime is 16821255809. The next prime is 16821255833. The reversal of 16821255828 is 82855212861.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1247113 + ... + 1260528.

Almost surely, 2^16821255828 is an apocalyptic number.

It is an amenable number.

16821255828 is an abundant number, since it is smaller than the sum of its proper divisors (26430553388).

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

16821255828 is a wasteful number, since it uses less digits than its factorization.

16821255828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2507704 (or 2507702 counting only the distinct ones).

The product of its digits is 614400, while the sum is 48.

The spelling of 16821255828 in words is "sixteen billion, eight hundred twenty-one million, two hundred fifty-five thousand, eight hundred twenty-eight".