1666694 has 4 divisors (see below), whose sum is σ = 2500044. Its totient is φ = 833346.

The previous prime is 1666657. The next prime is 1666711. The reversal of 1666694 is 4966661.

It is a semiprime because it is the product of two primes.

It is a congruent number.

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, 416672 + ... + 416675.

It is an arithmetic number, because the mean of its divisors is an integer number (625011).

2^1666694 is an apocalyptic number.

1666694 is a deficient number, since it is larger than the sum of its proper divisors (833350).

1666694 is an equidigital number, since it uses as much as digits as its factorization.

1666694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 833349.

The product of its digits is 46656, while the sum is 38.

The square root of 1666694 is about 1291.0050348469. The cubic root of 1666694 is about 118.5637582911.

The spelling of 1666694 in words is "one million, six hundred sixty-six thousand, six hundred ninety-four".