1981973721024 has 896 divisors, whose sum is σ = 6936828595200. Its totient is φ = 548093952000.

The previous prime is 1981973720989. The next prime is 1981973721029. The reversal of 1981973721024 is 4201273791891.

1981973721024 is a `hidden beast` number, since 1 + 9 + 81 + 97 + 372 + 102 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981973721029) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2795449182 + ... + 2795449890.

It is an arithmetic number, because the mean of its divisors is an integer number (7741996200).

Almost surely, 2^{1981973721024} 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 1981973721024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3468414297600).

1981973721024 is an abundant number, since it is smaller than the sum of its proper divisors (4954854874176).

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

1981973721024 is a wasteful number, since it uses less digits than its factorization.

1981973721024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1010 (or 994 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 54.

The spelling of 1981973721024 in words is "one trillion, nine hundred eighty-one billion, nine hundred seventy-three million, seven hundred twenty-one thousand, twenty-four".