1666325378016 has 288 divisors, whose sum is σ = 5265271589760. Its totient is φ = 496669335552.

The previous prime is 1666325377919. The next prime is 1666325378087. The reversal of 1666325378016 is 6108735236661.

It is a tau number, because it is divible by the number of its divisors (288).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15622980 + ... + 15729276.

It is an arithmetic number, because the mean of its divisors is an integer number (18282193020).

Almost surely, 2^{1666325378016} is an apocalyptic number.

1666325378016 is a gapful number since it is divisible by the number (16) 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 1666325378016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2632635794880).

1666325378016 is an abundant number, since it is smaller than the sum of its proper divisors (3598946211744).

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

1666325378016 is a wasteful number, since it uses less digits than its factorization.

1666325378016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106458 (or 106447 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 54.

The spelling of 1666325378016 in words is "one trillion, six hundred sixty-six billion, three hundred twenty-five million, three hundred seventy-eight thousand, sixteen".