19989120 has 128 divisors (see below), whose sum is σ = 66096000. Its totient is φ = 5132288.

The previous prime is 19989113. The next prime is 19989131. The reversal of 19989120 is 2198991.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55501 + ... + 55859.

It is an arithmetic number, because the mean of its divisors is an integer number (516375).

Almost surely, 2^19989120 is an apocalyptic number.

19989120 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 19989120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33048000).

19989120 is an abundant number, since it is smaller than the sum of its proper divisors (46106880).

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

19989120 is a wasteful number, since it uses less digits than its factorization.

19989120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 398 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 39.

The square root of 19989120 is about 4470.9193685416. The cubic root of 19989120 is about 271.3925312919.

The spelling of 19989120 in words is "nineteen million, nine hundred eighty-nine thousand, one hundred twenty".