999980000000 has 144 divisors (see below), whose sum is σ = 2495110800000. Its totient is φ = 399984000000.

The previous prime is 999979999987. The next prime is 999980000029. The reversal of 999980000000 is 89999.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 999979999897 and 999979999906.

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 15 ways as a sum of consecutive naturals, for example, 19975001 + ... + 20024999.

Almost surely, 2^999980000000 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 999980000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1247555400000).

999980000000 is an abundant number, since it is smaller than the sum of its proper divisors (1495130800000).

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

999980000000 is an frugal number, since it uses more digits than its factorization.

999980000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50050 (or 50006 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 44.

Adding to 999980000000 its reverse (89999), we get a palindrome (999980089999).

The spelling of 999980000000 in words is "nine hundred ninety-nine billion, nine hundred eighty million", and thus it is an aban number.