19980181986 has 32 divisors (see below), whose sum is σ = 40273504128. Its totient is φ = 6607977600.

The previous prime is 19980181981. The next prime is 19980181993. The reversal of 19980181986 is 68918108991.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19980181981) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 763576 + ... + 789308.

It is an arithmetic number, because the mean of its divisors is an integer number (1258547004).

Almost surely, 2^19980181986 is an apocalyptic number.

19980181986 is an abundant number, since it is smaller than the sum of its proper divisors (20293322142).

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

19980181986 is a wasteful number, since it uses less digits than its factorization.

19980181986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26746.

The product of its (nonzero) digits is 2239488, while the sum is 60.

The spelling of 19980181986 in words is "nineteen billion, nine hundred eighty million, one hundred eighty-one thousand, nine hundred eighty-six".