19687728 has 80 divisors (see below), whose sum is σ = 53425152. Its totient is φ = 6240000.

The previous prime is 19687727. The next prime is 19687753. The reversal of 19687728 is 82778691.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (19687727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 150223 + ... + 150353.

Almost surely, 2^19687728 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 19687728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26712576).

19687728 is an abundant number, since it is smaller than the sum of its proper divisors (33737424).

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

19687728 is a wasteful number, since it uses less digits than its factorization.

19687728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274 (or 268 counting only the distinct ones).

The product of its digits is 338688, while the sum is 48.

The square root of 19687728 is about 4437.0855299397. The cubic root of 19687728 is about 270.0216169249.

The spelling of 19687728 in words is "nineteen million, six hundred eighty-seven thousand, seven hundred twenty-eight".