1668671 has 4 divisors (see below), whose sum is σ = 1683552. Its totient is φ = 1653792.

The previous prime is 1668649. The next prime is 1668679. The reversal of 1668671 is 1768661.

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 1668671 - 2¹⁰ = 1667647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668679) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7271 + ... + 7496.

It is an arithmetic number, because the mean of its divisors is an integer number (420888).

2^1668671 is an apocalyptic number.

1668671 is a deficient number, since it is larger than the sum of its proper divisors (14881).

1668671 is a wasteful number, since it uses less digits than its factorization.

1668671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14880.

The product of its digits is 12096, while the sum is 35.

The square root of 1668671 is about 1291.7704904510. The cubic root of 1668671 is about 118.6106191088.

The spelling of 1668671 in words is "one million, six hundred sixty-eight thousand, six hundred seventy-one".