1665108900000 has 2016 divisors, whose sum is σ = 7591218880896. Its totient is φ = 349920000000.

The previous prime is 1665108899999. The next prime is 1665108900011. The reversal of 1665108900000 is 98015661.

1665108900000 is a `hidden beast` number, since 1 + 66 + 510 + 89 + 0 + 0 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2016).

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

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 335 ways as a sum of consecutive naturals, for example, 6633899875 + ... + 6633900125.

It is an arithmetic number, because the mean of its divisors is an integer number (3765485556).

Almost surely, 2^{1665108900000} is an apocalyptic number.

1665108900000 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 1665108900000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3795609440448).

1665108900000 is an abundant number, since it is smaller than the sum of its proper divisors (5926109980896).

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

1665108900000 is an frugal number, since it uses more digits than its factorization.

1665108900000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324 (or 281 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 1665108900000 in words is "one trillion, six hundred sixty-five billion, one hundred eight million, nine hundred thousand".