1668321684 has 60 divisors (see below), whose sum is σ = 4416596800. Its totient is φ = 549059472.

The previous prime is 1668321671. The next prime is 1668321689. The reversal of 1668321684 is 4861238661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668321689) 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 19 ways as a sum of consecutive naturals, for example, 6994 + ... + 58185.

Almost surely, 2^1668321684 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1668321684, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2208298400).

1668321684 is an abundant number, since it is smaller than the sum of its proper divisors (2748275116).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1668321684 is a wasteful number, since it uses less digits than its factorization.

1668321684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65274 (or 65263 counting only the distinct ones).

The product of its digits is 331776, while the sum is 45.

The square root of 1668321684 is about 40845.0937567782. The cubic root of 1668321684 is about 1186.0234196714.

The spelling of 1668321684 in words is "one billion, six hundred sixty-eight million, three hundred twenty-one thousand, six hundred eighty-four".