1666832173 has 2 divisors, whose sum is σ = 1666832174. Its totient is φ = 1666832172.

The previous prime is 1666832143. The next prime is 1666832191. The reversal of 1666832173 is 3712386661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1359986884 + 306845289 = 36878^2 + 17517^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666832173 - 2²¹ = 1664735021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666832113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833416086 + 833416087.

It is an arithmetic number, because the mean of its divisors is an integer number (833416087).

Almost surely, 2^1666832173 is an apocalyptic number.

It is an amenable number.

1666832173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666832173 is an equidigital number, since it uses as much as digits as its factorization.

1666832173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 43.

The square root of 1666832173 is about 40826.8560263952. The cubic root of 1666832173 is about 1185.6703460889.

It can be divided in two parts, 16668 and 32173, that added together give a square (48841 = 221²).

The spelling of 1666832173 in words is "one billion, six hundred sixty-six million, eight hundred thirty-two thousand, one hundred seventy-three".