1668667 has 16 divisors (see below), whose sum is σ = 2241792. Its totient is φ = 1199520.

The previous prime is 1668649. The next prime is 1668679. The reversal of 1668667 is 7668661.

It is not a de Polignac number, because 1668667 - 2⁷ = 1668539 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1668617) 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 15 ways as a sum of consecutive naturals, for example, 168 + ... + 1834.

It is an arithmetic number, because the mean of its divisors is an integer number (140112).

2^1668667 is an apocalyptic number.

1668667 is a deficient number, since it is larger than the sum of its proper divisors (573125).

1668667 is a wasteful number, since it uses less digits than its factorization.

1668667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1698.

The product of its digits is 72576, while the sum is 40.

The square root of 1668667 is about 1291.7689421874. The cubic root of 1668667 is about 118.6105243342.

The spelling of 1668667 in words is "one million, six hundred sixty-eight thousand, six hundred sixty-seven".