1668424 has 8 divisors (see below), whose sum is σ = 3128310. Its totient is φ = 834208.

The previous prime is 1668379. The next prime is 1668427. The reversal of 1668424 is 4248661.

It can be written as a sum of positive squares in only one way, i.e., 1483524 + 184900 = 1218^2 + 430^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (1668427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104269 + ... + 104284.

2^1668424 is an apocalyptic number.

It is an amenable number.

1668424 is a deficient number, since it is larger than the sum of its proper divisors (1459886).

1668424 is a wasteful number, since it uses less digits than its factorization.

1668424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208559 (or 208555 counting only the distinct ones).

The product of its digits is 9216, while the sum is 31.

The square root of 1668424 is about 1291.6748816943. The cubic root of 1668424 is about 118.6047664934.

The spelling of 1668424 in words is "one million, six hundred sixty-eight thousand, four hundred twenty-four".