1666444 has 24 divisors (see below), whose sum is σ = 3190880. Its totient is φ = 756864.

The previous prime is 1666429. The next prime is 1666447. The reversal of 1666444 is 4446661.

It is not an unprimeable number, because it can be changed into a prime (1666447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3577 + ... + 4015.

2^1666444 is an apocalyptic number.

It is an amenable number.

1666444 is a deficient number, since it is larger than the sum of its proper divisors (1524436).

1666444 is a wasteful number, since it uses less digits than its factorization.

1666444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529 (or 527 counting only the distinct ones).

The product of its digits is 13824, while the sum is 31.

The square root of 1666444 is about 1290.9082074261. The cubic root of 1666444 is about 118.5578299040.

The spelling of 1666444 in words is "one million, six hundred sixty-six thousand, four hundred forty-four".