19889128 has 64 divisors (see below), whose sum is σ = 45417600. Its totient is φ = 7983360.

The previous prime is 19889117. The next prime is 19889137. The reversal of 19889128 is 82198891.

It is a congruent number.

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, 59923 + ... + 60253.

It is an arithmetic number, because the mean of its divisors is an integer number (709650).

Almost surely, 2^19889128 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 19889128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22708800).

19889128 is an abundant number, since it is smaller than the sum of its proper divisors (25528472).

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

19889128 is a wasteful number, since it uses less digits than its factorization.

19889128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 406 counting only the distinct ones).

The product of its digits is 82944, while the sum is 46.

The square root of 19889128 is about 4459.7228613446. The cubic root of 19889128 is about 270.9392437430.

The spelling of 19889128 in words is "nineteen million, eight hundred eighty-nine thousand, one hundred twenty-eight".