19900385856 has 336 divisors, whose sum is σ = 64118605824. Its totient is φ = 6083444736.

The previous prime is 19900385837. The next prime is 19900385863. The reversal of 19900385856 is 65858300991.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 51959041 + ... + 51959423.

It is an arithmetic number, because the mean of its divisors is an integer number (190829184).

Almost surely, 2^19900385856 is an apocalyptic number.

19900385856 is a gapful number since it is divisible by the number (16) 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 19900385856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32059302912).

19900385856 is an abundant number, since it is smaller than the sum of its proper divisors (44218219968).

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

19900385856 is a wasteful number, since it uses less digits than its factorization.

19900385856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680 (or 658 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 54.

The spelling of 19900385856 in words is "nineteen billion, nine hundred million, three hundred eighty-five thousand, eight hundred fifty-six".