19845631836 has 108 divisors (see below), whose sum is σ = 54592928208. Its totient is φ = 6057552384.

The previous prime is 19845631823. The next prime is 19845631843. The reversal of 19845631836 is 63813654891.

19845631836 is a `hidden beast` number, since 1 + 9 + 8 + 456 + 3 + 183 + 6 = 666.

It is a congruent number.

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 35 ways as a sum of consecutive naturals, for example, 825985 + ... + 849671.

It is an arithmetic number, because the mean of its divisors is an integer number (505490076).

Almost surely, 2^19845631836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19845631836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27296464104).

19845631836 is an abundant number, since it is smaller than the sum of its proper divisors (34747296372).

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

19845631836 is a wasteful number, since it uses less digits than its factorization.

19845631836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23788 (or 23746 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 54.

The spelling of 19845631836 in words is "nineteen billion, eight hundred forty-five million, six hundred thirty-one thousand, eight hundred thirty-six".