19721119984 has 20 divisors (see below), whose sum is σ = 38420778760. Its totient is φ = 9806080320.

The previous prime is 19721119981. The next prime is 19721120021. The reversal of 19721119984 is 48991112791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19721119981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3401994 + ... + 3407785.

It is an arithmetic number, because the mean of its divisors is an integer number (1921038938).

Almost surely, 2^19721119984 is an apocalyptic number.

It is an amenable number.

19721119984 is a deficient number, since it is larger than the sum of its proper divisors (18699658776).

19721119984 is a wasteful number, since it uses less digits than its factorization.

19721119984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6809968 (or 6809962 counting only the distinct ones).

The product of its digits is 326592, while the sum is 52.

The spelling of 19721119984 in words is "nineteen billion, seven hundred twenty-one million, one hundred nineteen thousand, nine hundred eighty-four".