1666660285161 has 6 divisors (see below), whose sum is σ = 2407398189690. Its totient is φ = 1111106856768.

The previous prime is 1666660285153. The next prime is 1666660285237. The reversal of 1666660285161 is 1615820666661.

It can be written as a sum of positive squares in only one way, i.e., 989239106025 + 677421179136 = 994605^2 + 823056^2 .

It is not a de Polignac number, because 1666660285161 - 2³ = 1666660285153 is a prime.

It is a super-2 number, since 2×1666660285161² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1666660285098 and 1666660285107.

It is not an unprimeable number, because it can be changed into a prime (1666660285561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92592238056 + ... + 92592238073.

It is an arithmetic number, because the mean of its divisors is an integer number (401233031615).

Almost surely, 2^{1666660285161} is an apocalyptic number.

It is an amenable number.

1666660285161 is a deficient number, since it is larger than the sum of its proper divisors (740737904529).

1666660285161 is a wasteful number, since it uses less digits than its factorization.

1666660285161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185184476135 (or 185184476132 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 54.

The spelling of 1666660285161 in words is "one trillion, six hundred sixty-six billion, six hundred sixty million, two hundred eighty-five thousand, one hundred sixty-one".