20619984 has 120 divisors (see below), whose sum is σ = 67683168. Its totient is φ = 5349120.

The previous prime is 20619979. The next prime is 20620003. The reversal of 20619984 is 48991602.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25474 + ... + 26270.

Almost surely, 2^20619984 is an apocalyptic number.

20619984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20619984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33841584).

20619984 is an abundant number, since it is smaller than the sum of its proper divisors (47063184).

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

20619984 is a wasteful number, since it uses less digits than its factorization.

20619984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 833 (or 820 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 39.

The square root of 20619984 is about 4540.9232541412. The cubic root of 20619984 is about 274.2180940699.

The spelling of 20619984 in words is "twenty million, six hundred nineteen thousand, nine hundred eighty-four".