19985616 has 100 divisors (see below), whose sum is σ = 66137632. Its totient is φ = 5707584.

The previous prime is 19985599. The next prime is 19985617. The reversal of 19985616 is 61658991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19985617) by changing a digit.

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 19 ways as a sum of consecutive naturals, for example, 7971 + ... + 10173.

Almost surely, 2^19985616 is an apocalyptic number.

19985616 is a gapful number since it is divisible by the number (16) 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 19985616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33068816).

19985616 is an abundant number, since it is smaller than the sum of its proper divisors (46152016).

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

19985616 is a wasteful number, since it uses less digits than its factorization.

19985616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2230 (or 2215 counting only the distinct ones).

The product of its digits is 116640, while the sum is 45.

The square root of 19985616 is about 4470.5274856554. The cubic root of 19985616 is about 271.3766724146.

The spelling of 19985616 in words is "nineteen million, nine hundred eighty-five thousand, six hundred sixteen".