19121743872 has 576 divisors, whose sum is σ = 71547840000. Its totient is φ = 4956733440.

The previous prime is 19121743867. The next prime is 19121743903. The reversal of 19121743872 is 27834712191.

19121743872 is a `hidden beast` number, since 191 + 21 + 7 + 438 + 7 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 38319879 + ... + 38320377.

It is an arithmetic number, because the mean of its divisors is an integer number (124215000).

Almost surely, 2^19121743872 is an apocalyptic number.

19121743872 is a gapful number since it is divisible by the number (12) 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 19121743872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35773920000).

19121743872 is an abundant number, since it is smaller than the sum of its proper divisors (52426096128).

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

19121743872 is an equidigital number, since it uses as much as digits as its factorization.

19121743872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554 (or 522 counting only the distinct ones).

The product of its digits is 169344, while the sum is 45.

The spelling of 19121743872 in words is "nineteen billion, one hundred twenty-one million, seven hundred forty-three thousand, eight hundred seventy-two".