1666843361 has 8 divisors (see below), whose sum is σ = 1695636264. Its totient is φ = 1638097920.

The previous prime is 1666843351. The next prime is 1666843403. The reversal of 1666843361 is 1633486661.

It can be written as a sum of positive squares in 4 ways, for example, as 79299025 + 1587544336 = 8905^2 + 39844^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1666843361 - 2¹⁰ = 1666842337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1666843331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63011 + ... + 85463.

It is an arithmetic number, because the mean of its divisors is an integer number (211954533).

Almost surely, 2^1666843361 is an apocalyptic number.

It is an amenable number.

1666843361 is a deficient number, since it is larger than the sum of its proper divisors (28792903).

1666843361 is a wasteful number, since it uses less digits than its factorization.

1666843361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23731.

The product of its digits is 373248, while the sum is 44.

The square root of 1666843361 is about 40826.9930438184. The cubic root of 1666843361 is about 1185.6729988755.

The spelling of 1666843361 in words is "one billion, six hundred sixty-six million, eight hundred forty-three thousand, three hundred sixty-one".