819844909424640 has 2016 divisors, whose sum is σ = 3303446675832576. Its totient is φ = 187634810880000.

The previous prime is 819844909424579. The next prime is 819844909424657. The reversal of 819844909424640 is 46424909448918.

819844909424640 is a `hidden beast` number, since 8 + 1 + 9 + 8 + 4 + 490 + 94 + 2 + 4 + 6 + 40 = 666.

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

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 143 ways as a sum of consecutive naturals, for example, 56693507010 + ... + 56693521470.

It is an arithmetic number, because the mean of its divisors is an integer number (1638614422536).

Almost surely, 2^{819844909424640} is an apocalyptic number.

819844909424640 is a gapful number since it is divisible by the number (80) 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 819844909424640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1651723337916288).

819844909424640 is an abundant number, since it is smaller than the sum of its proper divisors (2483601766407936).

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

819844909424640 is a wasteful number, since it uses less digits than its factorization.

819844909424640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14592 (or 14554 counting only the distinct ones).

The product of its (nonzero) digits is 573308928, while the sum is 72.

The spelling of 819844909424640 in words is "eight hundred nineteen trillion, eight hundred forty-four billion, nine hundred nine million, four hundred twenty-four thousand, six hundred forty".