1668111 has 4 divisors (see below), whose sum is σ = 2224152. Its totient is φ = 1112072.

The previous prime is 1668089. The next prime is 1668113. The reversal of 1668111 is 1118661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1668111 - 2⁹ = 1667599 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 278016 + ... + 278021.

It is an arithmetic number, because the mean of its divisors is an integer number (556038).

2^1668111 is an apocalyptic number.

1668111 is a deficient number, since it is larger than the sum of its proper divisors (556041).

1668111 is an equidigital number, since it uses as much as digits as its factorization.

1668111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556040.

The product of its digits is 288, while the sum is 24.

The square root of 1668111 is about 1291.5537154915. The cubic root of 1668111 is about 118.5973491915.

The spelling of 1668111 in words is "one million, six hundred sixty-eight thousand, one hundred eleven".