1666297 has 2 divisors, whose sum is σ = 1666298. Its totient is φ = 1666296.

The previous prime is 1666279. The next prime is 1666303. The reversal of 1666297 is 7926661.

Together with previous prime (1666279) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1590121 + 76176 = 1261^2 + 276^2 .

It is an emirp because it is prime and its reverse (7926661) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1666297 is a prime.

It is not a weakly prime, because it can be changed into another prime (1666237) by changing a digit.

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

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833148 + 833149.

It is an arithmetic number, because the mean of its divisors is an integer number (833149).

2^1666297 is an apocalyptic number.

It is an amenable number.

1666297 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666297 is an equidigital number, since it uses as much as digits as its factorization.

1666297 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 37.

The square root of 1666297 is about 1290.8512695117. The cubic root of 1666297 is about 118.5543437356.

The spelling of 1666297 in words is "one million, six hundred sixty-six thousand, two hundred ninety-seven".