1668911 has 2 divisors, whose sum is σ = 1668912. Its totient is φ = 1668910.

The previous prime is 1668889. The next prime is 1668913. The reversal of 1668911 is 1198661.

It is a strong prime.

It is an emirp because it is prime and its reverse (1198661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1668911 - 2⁶ = 1668847 is a prime.

It is a Sophie Germain prime.

Together with 1668913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834455 + 834456.

It is an arithmetic number, because the mean of its divisors is an integer number (834456).

2^1668911 is an apocalyptic number.

1668911 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668911 is an equidigital number, since it uses as much as digits as its factorization.

1668911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 32.

The square root of 1668911 is about 1291.8633828699. The cubic root of 1668911 is about 118.6163053073.

The spelling of 1668911 in words is "one million, six hundred sixty-eight thousand, nine hundred eleven".