20663984 has 40 divisors (see below), whose sum is σ = 44046288. Its totient is φ = 9313280.

The previous prime is 20663977. The next prime is 20663987. The reversal of 20663984 is 48936602.

It is not an unprimeable number, because it can be changed into a prime (20663987) 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 in 7 ways as a sum of consecutive naturals, for example, 23684 + ... + 24540.

Almost surely, 2^20663984 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 20663984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22023144).

20663984 is an abundant number, since it is smaller than the sum of its proper divisors (23382304).

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

20663984 is a wasteful number, since it uses less digits than its factorization.

20663984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1013 (or 1007 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 38.

The square root of 20663984 is about 4545.7655020909. The cubic root of 20663984 is about 274.4130024693.

The spelling of 20663984 in words is "twenty million, six hundred sixty-three thousand, nine hundred eighty-four".