1666693 has 4 divisors (see below), whose sum is σ = 1904800. Its totient is φ = 1428588.

The previous prime is 1666657. The next prime is 1666711. The reversal of 1666693 is 3966661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1666693 - 2¹⁷ = 1535621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666393) 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 3 ways as a sum of consecutive naturals, for example, 119043 + ... + 119056.

It is an arithmetic number, because the mean of its divisors is an integer number (476200).

2^1666693 is an apocalyptic number.

It is an amenable number.

1666693 is a deficient number, since it is larger than the sum of its proper divisors (238107).

1666693 is an equidigital number, since it uses as much as digits as its factorization.

1666693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238106.

The product of its digits is 34992, while the sum is 37.

The square root of 1666693 is about 1291.0046475517. The cubic root of 1666693 is about 118.5637345788.

Subtracting 1666693 from its reverse (3966661), we obtain a cube (2299968 = 132³).

It can be divided in two parts, 166 and 6693, that added together give a cube (6859 = 19³).

The spelling of 1666693 in words is "one million, six hundred sixty-six thousand, six hundred ninety-three".