19720555392 has 128 divisors (see below), whose sum is σ = 55657238400. Its totient is φ = 6169098240.

The previous prime is 19720555391. The next prime is 19720555397. The reversal of 19720555392 is 29355502791.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19720555391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 768042 + ... + 793302.

It is an arithmetic number, because the mean of its divisors is an integer number (434822175).

Almost surely, 2^19720555392 is an apocalyptic number.

19720555392 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 19720555392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27828619200).

19720555392 is an abundant number, since it is smaller than the sum of its proper divisors (35936683008).

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

19720555392 is a wasteful number, since it uses less digits than its factorization.

19720555392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25404 (or 25392 counting only the distinct ones).

The product of its (nonzero) digits is 850500, while the sum is 48.

The spelling of 19720555392 in words is "nineteen billion, seven hundred twenty million, five hundred fifty-five thousand, three hundred ninety-two".