1981980000000 has 2592 divisors, whose sum is σ = 9663464323968. Its totient is φ = 380160000000.

The previous prime is 1981979999983. The next prime is 1981980000001. The reversal of 1981980000000 is 891891.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1981980000000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981980000001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 152459999994 + ... + 152460000006.

Almost surely, 2^{1981980000000} is an apocalyptic number.

1981980000000 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 1981980000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4831732161984).

1981980000000 is an abundant number, since it is smaller than the sum of its proper divisors (7681484323968).

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

1981980000000 is an frugal number, since it uses more digits than its factorization.

1981980000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

Adding to 1981980000000 its reverse (891891), we get a palindrome (1981980891891).

The spelling of 1981980000000 in words is "one trillion, nine hundred eighty-one billion, nine hundred eighty million", and thus it is an aban number.