19916449920 has 192 divisors, whose sum is σ = 68857588800. Its totient is φ = 5304600576.

The previous prime is 19916449837. The next prime is 19916449921. The reversal of 19916449920 is 2994461991.

19916449920 is a `hidden beast` number, since 1 + 9 + 91 + 64 + 499 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is not an unprimeable number, because it can be changed into a prime (19916449921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6466941 + ... + 6470019.

It is an arithmetic number, because the mean of its divisors is an integer number (358633275).

Almost surely, 2^19916449920 is an apocalyptic number.

19916449920 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 19916449920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34428794400).

19916449920 is an abundant number, since it is smaller than the sum of its proper divisors (48941138880).

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

19916449920 is a wasteful number, since it uses less digits than its factorization.

19916449920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4227 (or 4212 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 54.

The spelling of 19916449920 in words is "nineteen billion, nine hundred sixteen million, four hundred forty-nine thousand, nine hundred twenty".