1781441661024 has 144 divisors (see below), whose sum is σ = 5081492025792. Its totient is φ = 591996708864.

The previous prime is 1781441660989. The next prime is 1781441661047. The reversal of 1781441661024 is 4201661441871.

1781441661024 is a `hidden beast` number, since 1 + 7 + 8 + 1 + 4 + 4 + 1 + 6 + 610 + 24 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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 23 ways as a sum of consecutive naturals, for example, 310190697 + ... + 310196439.

It is an arithmetic number, because the mean of its divisors is an integer number (35288139068).

Almost surely, 2^{1781441661024} 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 1781441661024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2540746012896).

1781441661024 is an abundant number, since it is smaller than the sum of its proper divisors (3300050364768).

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

1781441661024 is a wasteful number, since it uses less digits than its factorization.

1781441661024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8869 (or 8858 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The spelling of 1781441661024 in words is "one trillion, seven hundred eighty-one billion, four hundred forty-one million, six hundred sixty-one thousand, twenty-four".