19905618852 has 144 divisors (see below), whose sum is σ = 60976685952. Its totient is φ = 5344957440.

The previous prime is 19905618833. The next prime is 19905618853. The reversal of 19905618852 is 25881650991.

19905618852 is a `hidden beast` number, since 19 + 9 + 0 + 5 + 618 + 8 + 5 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (19905618853) 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 47 ways as a sum of consecutive naturals, for example, 3308527 + ... + 3314537.

It is an arithmetic number, because the mean of its divisors is an integer number (423449208).

Almost surely, 2^19905618852 is an apocalyptic number.

19905618852 is a gapful number since it is divisible by the number (12) 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 19905618852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30488342976).

19905618852 is an abundant number, since it is smaller than the sum of its proper divisors (41071067100).

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

19905618852 is a wasteful number, since it uses less digits than its factorization.

19905618852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6818 (or 6813 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 54.

The spelling of 19905618852 in words is "nineteen billion, nine hundred five million, six hundred eighteen thousand, eight hundred fifty-two".