19728688 has 80 divisors (see below), whose sum is σ = 46981120. Its totient is φ = 7838208.

The previous prime is 19728629. The next prime is 19728697. The reversal of 19728688 is 88682791.

It is a super-2 number, since 2×19728688² = 778442260402688, which contains 22 as substring.

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, 155281 + ... + 155407.

It is an arithmetic number, because the mean of its divisors is an integer number (587264).

Almost surely, 2^19728688 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 19728688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23490560).

19728688 is an abundant number, since it is smaller than the sum of its proper divisors (27252432).

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

19728688 is a wasteful number, since it uses less digits than its factorization.

19728688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234 (or 228 counting only the distinct ones).

The product of its digits is 387072, while the sum is 49.

The square root of 19728688 is about 4441.6987741178. The cubic root of 19728688 is about 270.2087457491.

The spelling of 19728688 in words is "nineteen million, seven hundred twenty-eight thousand, six hundred eighty-eight".