19887900856320 has 1664 divisors, whose sum is σ = 80462932070400. Its totient is φ = 4175670804480.

The previous prime is 19887900856273. The next prime is 19887900856321. The reversal of 19887900856320 is 2365800978891.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (19887900856321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 15405034875 + ... + 15405036165.

Almost surely, 2^{19887900856320} is an apocalyptic number.

19887900856320 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 19887900856320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40231466035200).

19887900856320 is an abundant number, since it is smaller than the sum of its proper divisors (60575031214080).

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

19887900856320 is a wasteful number, since it uses less digits than its factorization.

19887900856320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1404 (or 1368 counting only the distinct ones).

The product of its (nonzero) digits is 52254720, while the sum is 66.

The spelling of 19887900856320 in words is "nineteen trillion, eight hundred eighty-seven billion, nine hundred million, eight hundred fifty-six thousand, three hundred twenty".