1821844057440 has 384 divisors, whose sum is σ = 6399116494848. Its totient is φ = 431897518080.

The previous prime is 1821844057421. The next prime is 1821844057463. The reversal of 1821844057440 is 447504481281.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 1821844057440.

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 63 ways as a sum of consecutive naturals, for example, 396309222 + ... + 396313818.

It is an arithmetic number, because the mean of its divisors is an integer number (16664365872).

Almost surely, 2^{1821844057440} is an apocalyptic number.

1821844057440 is a gapful number since it is divisible by the number (10) 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 1821844057440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3199558247424).

1821844057440 is an abundant number, since it is smaller than the sum of its proper divisors (4577272437408).

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

1821844057440 is a wasteful number, since it uses less digits than its factorization.

1821844057440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6270 (or 6262 counting only the distinct ones).

The product of its (nonzero) digits is 1146880, while the sum is 48.

The spelling of 1821844057440 in words is "one trillion, eight hundred twenty-one billion, eight hundred forty-four million, fifty-seven thousand, four hundred forty".