19794018816 has 1280 divisors, whose sum is σ = 79194931200. Its totient is φ = 4777574400.

The previous prime is 19794018779. The next prime is 19794018823. The reversal of 19794018816 is 61881049791.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 638516721 + ... + 638516751.

It is an arithmetic number, because the mean of its divisors is an integer number (61871040).

Almost surely, 2^19794018816 is an apocalyptic number.

19794018816 is a gapful number since it is divisible by the number (16) 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 19794018816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39597465600).

19794018816 is an abundant number, since it is smaller than the sum of its proper divisors (59400912384).

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

19794018816 is a wasteful number, since it uses less digits than its factorization.

19794018816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 54.

The spelling of 19794018816 in words is "nineteen billion, seven hundred ninety-four million, eighteen thousand, eight hundred sixteen".