19821996085 has 4 divisors (see below), whose sum is σ = 23786395308. Its totient is φ = 15857596864.

The previous prime is 19821996083. The next prime is 19821996121. The reversal of 19821996085 is 58069912891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4435826404 + 15386169681 = 66602^2 + 124041^2 .

It is a cyclic number.

It is not a de Polignac number, because 19821996085 - 2¹ = 19821996083 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19821996083) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1982199604 + ... + 1982199613.

It is an arithmetic number, because the mean of its divisors is an integer number (5946598827).

Almost surely, 2^19821996085 is an apocalyptic number.

It is an amenable number.

19821996085 is a deficient number, since it is larger than the sum of its proper divisors (3964399223).

19821996085 is an equidigital number, since it uses as much as digits as its factorization.

19821996085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3964399222.

The product of its (nonzero) digits is 2799360, while the sum is 58.

The spelling of 19821996085 in words is "nineteen billion, eight hundred twenty-one million, nine hundred ninety-six thousand, eighty-five".