19887736680 has 256 divisors, whose sum is σ = 75865190400. Its totient is φ = 4539628800.

The previous prime is 19887736679. The next prime is 19887736691. The reversal of 19887736680 is 8663778891.

19887736680 is a `hidden beast` number, since 198 + 8 + 7 + 7 + 366 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7944309 + ... + 7946811.

It is an arithmetic number, because the mean of its divisors is an integer number (296348400).

Almost surely, 2^19887736680 is an apocalyptic number.

19887736680 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 19887736680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37932595200).

19887736680 is an abundant number, since it is smaller than the sum of its proper divisors (55977453720).

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

19887736680 is a wasteful number, since it uses less digits than its factorization.

19887736680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3581 (or 3571 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 63.

The spelling of 19887736680 in words is "nineteen billion, eight hundred eighty-seven million, seven hundred thirty-six thousand, six hundred eighty".