1668439406 has 16 divisors (see below), whose sum is σ = 2627182080. Its totient is φ = 793624440.

The previous prime is 1668439391. The next prime is 1668439441. The reversal of 1668439406 is 6049348661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 224396 + ... + 231711.

It is an arithmetic number, because the mean of its divisors is an integer number (164198880).

Almost surely, 2^1668439406 is an apocalyptic number.

1668439406 is a deficient number, since it is larger than the sum of its proper divisors (958742674).

1668439406 is a wasteful number, since it uses less digits than its factorization.

1668439406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456199.

The product of its (nonzero) digits is 746496, while the sum is 47.

The square root of 1668439406 is about 40846.5348101892. The cubic root of 1668439406 is about 1186.0513155236.

The spelling of 1668439406 in words is "one billion, six hundred sixty-eight million, four hundred thirty-nine thousand, four hundred six".