1668679 has 2 divisors, whose sum is σ = 1668680. Its totient is φ = 1668678.

The previous prime is 1668649. The next prime is 1668683. The reversal of 1668679 is 9768661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1668679 - 2⁵ = 1668647 is a prime.

It is a nialpdrome in base 6.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834339 + 834340.

It is an arithmetic number, because the mean of its divisors is an integer number (834340).

2^1668679 is an apocalyptic number.

1668679 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668679 is an equidigital number, since it uses as much as digits as its factorization.

1668679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 43.

The square root of 1668679 is about 1291.7735869726. The cubic root of 1668679 is about 118.6108086575.

The spelling of 1668679 in words is "one million, six hundred sixty-eight thousand, six hundred seventy-nine".