1666664 has 8 divisors (see below), whose sum is σ = 3125010. Its totient is φ = 833328.

The previous prime is 1666657. The next prime is 1666711. The reversal of 1666664 is 4666661.

It can be written as a sum of positive squares in only one way, i.e., 1582564 + 84100 = 1258^2 + 290^2 .

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

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 104159 + ... + 104174.

2^1666664 is an apocalyptic number.

It is an amenable number.

1666664 is a deficient number, since it is larger than the sum of its proper divisors (1458346).

1666664 is a wasteful number, since it uses less digits than its factorization.

1666664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208339 (or 208335 counting only the distinct ones).

The product of its digits is 31104, while the sum is 35.

The square root of 1666664 is about 1290.9934159398. The cubic root of 1666664 is about 118.5630469160.

The spelling of 1666664 in words is "one million, six hundred sixty-six thousand, six hundred sixty-four".