19866680660 has 24 divisors (see below), whose sum is σ = 41744513160. Its totient is φ = 7942008704.

The previous prime is 19866680593. The next prime is 19866680699. The reversal of 19866680660 is 6608666891.

It can be written as a sum of positive squares in 4 ways, for example, as 4328060944 + 15538619716 = 65788^2 + 124654^2 .

It is a junction number, because it is equal to n+sod(n) for n = 19866680596 and 19866680605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 256439 + ... + 324798.

It is an arithmetic number, because the mean of its divisors is an integer number (1739354715).

Almost surely, 2^19866680660 is an apocalyptic number.

19866680660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19866680660 is an abundant number, since it is smaller than the sum of its proper divisors (21877832500).

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

19866680660 is a wasteful number, since it uses less digits than its factorization.

19866680660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582955 (or 582953 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 56.

The spelling of 19866680660 in words is "nineteen billion, eight hundred sixty-six million, six hundred eighty thousand, six hundred sixty".