1998640980000 has 840 divisors, whose sum is σ = 8425644530688. Its totient is φ = 456808896000.

The previous prime is 1998640979921. The next prime is 1998640980031. The reversal of 1998640980000 is 890468991.

It is a tau number, because it is divible by the number of its divisors (840).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 139 ways as a sum of consecutive naturals, for example, 102050209 + ... + 102069791.

Almost surely, 2^{1998640980000} is an apocalyptic number.

1998640980000 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 1998640980000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4212822265344).

1998640980000 is an abundant number, since it is smaller than the sum of its proper divisors (6427003550688).

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

1998640980000 is an frugal number, since it uses more digits than its factorization.

1998640980000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19638 (or 19600 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 54.

The spelling of 1998640980000 in words is "one trillion, nine hundred ninety-eight billion, six hundred forty million, nine hundred eighty thousand".