1999879081200 has 3600 divisors, whose sum is σ = 10262079184896. Its totient is φ = 365957222400.

The previous prime is 1999879081181. The next prime is 1999879081243. The reversal of 1999879081200 is 21809789991.

1999879081200 is a `hidden beast` number, since 199 + 9 + 87 + 90 + 81 + 200 = 666.

It is a tau number, because it is divible by the number of its divisors (3600).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 719 ways as a sum of consecutive naturals, for example, 5221616209 + ... + 5221616591.

Almost surely, 2^{1999879081200} is an apocalyptic number.

1999879081200 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 1999879081200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5131039592448).

1999879081200 is an abundant number, since it is smaller than the sum of its proper divisors (8262200103696).

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

1999879081200 is a wasteful number, since it uses less digits than its factorization.

1999879081200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 5878656, while the sum is 63.

The spelling of 1999879081200 in words is "one trillion, nine hundred ninety-nine billion, eight hundred seventy-nine million, eighty-one thousand, two hundred".