19821638016 has 48 divisors (see below), whose sum is σ = 57038831460. Its totient is φ = 6607212288.

The previous prime is 19821637991. The next prime is 19821638017. The reversal of 19821638016 is 61083612891.

19821638016 is a `hidden beast` number, since 1 + 9 + 8 + 2 + 1 + 638 + 0 + 1 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19821638017) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8601990 + ... + 8604293.

Almost surely, 2^19821638016 is an apocalyptic number.

19821638016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

19821638016 is an abundant number, since it is smaller than the sum of its proper divisors (37217193444).

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

19821638016 is a wasteful number, since it uses less digits than its factorization.

19821638016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17206303 (or 17206288 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The spelling of 19821638016 in words is "nineteen billion, eight hundred twenty-one million, six hundred thirty-eight thousand, sixteen".