19989881280 has 672 divisors, whose sum is σ = 74982555648. Its totient is φ = 4877107200.

The previous prime is 19989881267. The next prime is 19989881299. The reversal of 19989881280 is 8218898991.

19989881280 is a `hidden beast` number, since 199 + 8 + 98 + 81 + 280 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 157400577 + ... + 157400703.

It is an arithmetic number, because the mean of its divisors is an integer number (111581184).

Almost surely, 2^19989881280 is an apocalyptic number.

19989881280 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 19989881280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37491277824).

19989881280 is an abundant number, since it is smaller than the sum of its proper divisors (54992674368).

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

19989881280 is a wasteful number, since it uses less digits than its factorization.

19989881280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265 (or 252 counting only the distinct ones).

The product of its (nonzero) digits is 5971968, while the sum is 63.

The spelling of 19989881280 in words is "nineteen billion, nine hundred eighty-nine million, eight hundred eighty-one thousand, two hundred eighty".