1666116661001 has 32 divisors (see below), whose sum is σ = 1895513114880. Its totient is φ = 1451774361600.

The previous prime is 1666116660997. The next prime is 1666116661049. The reversal of 1666116661001 is 1001666116661.

It is a cyclic number.

It is not a de Polignac number, because 1666116661001 - 2² = 1666116660997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1666116661001.

It is not an unprimeable number, because it can be changed into a prime (1666116661051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 79628021 + ... + 79648941.

It is an arithmetic number, because the mean of its divisors is an integer number (59234784840).

Almost surely, 2^{1666116661001} is an apocalyptic number.

It is an amenable number.

1666116661001 is a deficient number, since it is larger than the sum of its proper divisors (229396453879).

1666116661001 is a wasteful number, since it uses less digits than its factorization.

1666116661001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22097.

The product of its (nonzero) digits is 46656, while the sum is 41.

The spelling of 1666116661001 in words is "one trillion, six hundred sixty-six billion, one hundred sixteen million, six hundred sixty-one thousand, one".