19845778404672 has 336 divisors, whose sum is σ = 64377561343680. Its totient is φ = 5790029414400.

The previous prime is 19845778404637. The next prime is 19845778404703. The reversal of 19845778404672 is 27640487754891.

19845778404672 is a `hidden beast` number, since 1 + 9 + 8 + 4 + 57 + 78 + 40 + 467 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 19845778404672.

It is a congruent number.

It is an unprimeable number.

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, 64708647 + ... + 65014617.

Almost surely, 2^{19845778404672} is an apocalyptic number.

19845778404672 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 19845778404672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32188780671840).

19845778404672 is an abundant number, since it is smaller than the sum of its proper divisors (44531782939008).

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

19845778404672 is a wasteful number, since it uses less digits than its factorization.

19845778404672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306382 (or 306369 counting only the distinct ones).

The product of its (nonzero) digits is 758661120, while the sum is 72.

The spelling of 19845778404672 in words is "nineteen trillion, eight hundred forty-five billion, seven hundred seventy-eight million, four hundred four thousand, six hundred seventy-two".