1666965059712 has 320 divisors, whose sum is σ = 5078806064640. Its totient is φ = 542502420480.

The previous prime is 1666965059653. The next prime is 1666965059713. The reversal of 1666965059712 is 2179505696661.

It is a self number, because there is not a number n which added to its sum of digits gives 1666965059712.

It is not an unprimeable number, because it can be changed into a prime (1666965059713) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 210020608 + ... + 210028544.

It is an arithmetic number, because the mean of its divisors is an integer number (15871268952).

Almost surely, 2^{1666965059712} is an apocalyptic number.

1666965059712 is a gapful number since it is divisible by the number (12) 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 1666965059712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2539403032320).

1666965059712 is an abundant number, since it is smaller than the sum of its proper divisors (3411841004928).

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

1666965059712 is an equidigital number, since it uses as much as digits as its factorization.

1666965059712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8441 (or 8420 counting only the distinct ones).

The product of its (nonzero) digits is 36741600, while the sum is 63.

The spelling of 1666965059712 in words is "one trillion, six hundred sixty-six billion, nine hundred sixty-five million, fifty-nine thousand, seven hundred twelve".