20191104639720 has 1024 divisors, whose sum is σ = 83674791936000. Its totient is φ = 4226305766400.

The previous prime is 20191104639703. The next prime is 20191104639721. The reversal of 20191104639720 is 2793640119102.

20191104639720 is a `hidden beast` number, since 2 + 0 + 1 + 9 + 1 + 1 + 0 + 4 + 639 + 7 + 2 + 0 = 666.

20191104639720 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×20191104639720² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (20191104639721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 4911480465 + ... + 4911484575.

It is an arithmetic number, because the mean of its divisors is an integer number (81713664000).

Almost surely, 2^{20191104639720} is an apocalyptic number.

20191104639720 is a gapful number since it is divisible by the number (20) 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 20191104639720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41837395968000).

20191104639720 is an abundant number, since it is smaller than the sum of its proper divisors (63483687296280).

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

20191104639720 is a wasteful number, since it uses less digits than its factorization.

20191104639720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5291 (or 5281 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The spelling of 20191104639720 in words is "twenty trillion, one hundred ninety-one billion, one hundred four million, six hundred thirty-nine thousand, seven hundred twenty".