19744126818 has 128 divisors (see below), whose sum is σ = 43957976832. Its totient is φ = 5875408896.

The previous prime is 19744126817. The next prime is 19744126819. The reversal of 19744126818 is 81862144791.

It is an interprime number because it is at equal distance from previous prime (19744126817) and next prime (19744126819).

It is not an unprimeable number, because it can be changed into a prime (19744126817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 100223896 + ... + 100224092.

It is an arithmetic number, because the mean of its divisors is an integer number (343421694).

Almost surely, 2^19744126818 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19744126818, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21978988416).

19744126818 is an abundant number, since it is smaller than the sum of its proper divisors (24213850014).

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

19744126818 is a wasteful number, since it uses less digits than its factorization.

19744126818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548.

The product of its digits is 774144, while the sum is 51.

The spelling of 19744126818 in words is "nineteen billion, seven hundred forty-four million, one hundred twenty-six thousand, eight hundred eighteen".