19778998680 has 192 divisors, whose sum is σ = 74669774400. Its totient is φ = 4446766080.

The previous prime is 19778998633. The next prime is 19778998693. The reversal of 19778998680 is 8689987791.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 19778998599 and 19778998608.

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 47 ways as a sum of consecutive naturals, for example, 89386 + ... + 218054.

It is an arithmetic number, because the mean of its divisors is an integer number (388905075).

Almost surely, 2^19778998680 is an apocalyptic number.

19778998680 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 19778998680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37334887200).

19778998680 is an abundant number, since it is smaller than the sum of its proper divisors (54890775720).

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

19778998680 is a wasteful number, since it uses less digits than its factorization.

19778998680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128754 (or 128747 counting only the distinct ones).

The product of its (nonzero) digits is 109734912, while the sum is 72.

The spelling of 19778998680 in words is "nineteen billion, seven hundred seventy-eight million, nine hundred ninety-eight thousand, six hundred eighty".