19885720320 has 504 divisors, whose sum is σ = 72465008112. Its totient is φ = 5225472000.

The previous prime is 19885720289. The next prime is 19885720331. The reversal of 19885720320 is 2302758891.

It is a happy number.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 94245015 + ... + 94245225.

It is an arithmetic number, because the mean of its divisors is an integer number (143779778).

Almost surely, 2^19885720320 is an apocalyptic number.

19885720320 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 19885720320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36232504056).

19885720320 is an abundant number, since it is smaller than the sum of its proper divisors (52579287792).

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

19885720320 is an equidigital number, since it uses as much as digits as its factorization.

19885720320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 322 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 19885720320 in words is "nineteen billion, eight hundred eighty-five million, seven hundred twenty thousand, three hundred twenty".