19718977960 has 128 divisors (see below), whose sum is σ = 51674163840. Its totient is φ = 6748431360.

The previous prime is 19718977951. The next prime is 19718977997. The reversal of 19718977960 is 6977981791.

It is a junction number, because it is equal to n+sod(n) for n = 19718977892 and 19718977901.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 894187 + ... + 915973.

It is an arithmetic number, because the mean of its divisors is an integer number (403704405).

Almost surely, 2^19718977960 is an apocalyptic number.

19718977960 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 19718977960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25837081920).

19718977960 is an abundant number, since it is smaller than the sum of its proper divisors (31955185880).

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

19718977960 is a wasteful number, since it uses less digits than its factorization.

19718977960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21848 (or 21822 counting only the distinct ones).

The product of its (nonzero) digits is 12002256, while the sum is 64.

The spelling of 19718977960 in words is "nineteen billion, seven hundred eighteen million, nine hundred seventy-seven thousand, nine hundred sixty".