1999999000000 has 392 divisors, whose sum is σ = 5329883651616. Its totient is φ = 741888000000.

The previous prime is 1999998999989. The next prime is 1999999000007. The reversal of 1999999000000 is 9999991.

It is a happy number.

1999999000000 is a nontrivial binomial coefficient, being equal to C(2000000, 2).

1999999000000 is an astonishing number since 1999999000000 = 0 + ... + 1999999.

It is a junction number, because it is equal to n+sod(n) for n = 1999998999896 and 1999998999905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999999000007) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 1206999172 + ... + 1207000828.

Almost surely, 2^{1999999000000} is an apocalyptic number.

1999999000000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1999999000000 is the 1999999-th triangular number and also the 1000000-th hexagonal number.

1999999000000 is the 666667-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1999999000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2664941825808).

1999999000000 is an abundant number, since it is smaller than the sum of its proper divisors (3329884651616).

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

1999999000000 is an frugal number, since it uses more digits than its factorization.

1999999000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1787 (or 1752 counting only the distinct ones).

The product of its (nonzero) digits is 531441, while the sum is 55.

The spelling of 1999999000000 in words is "one trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million", and thus it is an aban number.