19864728 has 96 divisors (see below), whose sum is σ = 61042800. Its totient is φ = 5785344.

The previous prime is 19864723. The next prime is 19864759. The reversal of 19864728 is 82746891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19864723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17226 + ... + 18342.

Almost surely, 2^19864728 is an apocalyptic number.

19864728 is a gapful number since it is divisible by the number (18) 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 19864728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30521400).

19864728 is an abundant number, since it is smaller than the sum of its proper divisors (41178072).

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

19864728 is a wasteful number, since it uses less digits than its factorization.

19864728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1161 (or 1154 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 19864728 is about 4456.9864258263. The cubic root of 19864728 is about 270.8284022350.

The spelling of 19864728 in words is "nineteen million, eight hundred sixty-four thousand, seven hundred twenty-eight".