16681984 has 44 divisors (see below), whose sum is σ = 36403848. Its totient is φ = 7577600.

The previous prime is 16681949. The next prime is 16681991. The reversal of 16681984 is 48918661.

It is a tau number, because it is divible by the number of its divisors (44).

It is a self number, because there is not a number n which added to its sum of digits gives 16681984.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10524 + ... + 12004.

Almost surely, 2^16681984 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 16681984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18201924).

16681984 is an abundant number, since it is smaller than the sum of its proper divisors (19721864).

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

16681984 is a wasteful number, since it uses less digits than its factorization.

16681984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1512 (or 1494 counting only the distinct ones).

The product of its digits is 82944, while the sum is 43.

The square root of 16681984 is about 4084.3584563552. The cubic root of 16681984 is about 255.5147056179.

The spelling of 16681984 in words is "sixteen million, six hundred eighty-one thousand, nine hundred eighty-four".