19788733440 has 528 divisors, whose sum is σ = 80931502080. Its totient is φ = 4375019520.

The previous prime is 19788733427. The next prime is 19788733441. The reversal of 19788733440 is 4433788791.

19788733440 is a `hidden beast` number, since 1 + 97 + 8 + 87 + 33 + 440 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19788733441) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9998371 + ... + 10000349.

It is an arithmetic number, because the mean of its divisors is an integer number (153279360).

Almost surely, 2^19788733440 is an apocalyptic number.

19788733440 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 19788733440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40465751040).

19788733440 is an abundant number, since it is smaller than the sum of its proper divisors (61142768640).

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

19788733440 is a wasteful number, since it uses less digits than its factorization.

19788733440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2048 (or 2027 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 54.

The spelling of 19788733440 in words is "nineteen billion, seven hundred eighty-eight million, seven hundred thirty-three thousand, four hundred forty".