19988144 has 30 divisors (see below), whose sum is σ = 42373404. Its totient is φ = 9058560.

The previous prime is 19988131. The next prime is 19988153. The reversal of 19988144 is 44188991.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 19988095 and 19988104.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 59144 + ... + 59480.

Almost surely, 2^19988144 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 19988144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21186702).

19988144 is an abundant number, since it is smaller than the sum of its proper divisors (22385260).

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

19988144 is an equidigital number, since it uses as much as digits as its factorization.

19988144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693 (or 350 counting only the distinct ones).

The product of its digits is 82944, while the sum is 44.

The square root of 19988144 is about 4470.8102173991. The cubic root of 19988144 is about 271.3881141652.

Multiplying 19988144 by its sum of digits (44), we get a square (879478336 = 29656²).

19988144 divided by its sum of digits (44) gives a square (454276 = 674²).

The spelling of 19988144 in words is "nineteen million, nine hundred eighty-eight thousand, one hundred forty-four".