16921984 has 32 divisors (see below), whose sum is σ = 34192440. Its totient is φ = 8340480.

The previous prime is 16921981. The next prime is 16922023. The reversal of 16921984 is 48912961.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16921981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8439 + ... + 10249.

Almost surely, 2^16921984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16921984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17096220).

16921984 is an abundant number, since it is smaller than the sum of its proper divisors (17270456).

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

16921984 is an equidigital number, since it uses as much as digits as its factorization.

With its predecessor (16921983) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (1898).

16921984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1898 (or 1886 counting only the distinct ones).

The product of its digits is 31104, while the sum is 40.

The square root of 16921984 is about 4113.6339166241. The cubic root of 16921984 is about 256.7342203326.

The spelling of 16921984 in words is "sixteen million, nine hundred twenty-one thousand, nine hundred eighty-four".