19988000 has 96 divisors (see below), whose sum is σ = 51891840. Its totient is φ = 7545600.

The previous prime is 19987999. The next prime is 19988009. The reversal of 19988000 is 88991.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19988009) 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 15 ways as a sum of consecutive naturals, for example, 75869 + ... + 76131.

It is an arithmetic number, because the mean of its divisors is an integer number (540540).

Almost surely, 2^19988000 is an apocalyptic number.

19988000 is a gapful number since it is divisible by the number (10) 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 19988000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25945920).

19988000 is an abundant number, since it is smaller than the sum of its proper divisors (31903840).

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

19988000 is a wasteful number, since it uses less digits than its factorization.

19988000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 289 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 35.

The square root of 19988000 is about 4470.7941129066. The cubic root of 19988000 is about 271.3874624459.

The spelling of 19988000 in words is "nineteen million, nine hundred eighty-eight thousand".