1669693 has 4 divisors (see below), whose sum is σ = 1672380. Its totient is φ = 1667008.

The previous prime is 1669687. The next prime is 1669697. The reversal of 1669693 is 3969661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3969661 = 41 ⋅96821.

It can be written as a sum of positive squares in 2 ways, for example, as 994009 + 675684 = 997^2 + 822^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1669693 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

1669693 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1669697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 123 + ... + 1831.

It is an arithmetic number, because the mean of its divisors is an integer number (418095).

2^1669693 is an apocalyptic number.

It is an amenable number.

1669693 is a deficient number, since it is larger than the sum of its proper divisors (2687).

1669693 is an equidigital number, since it uses as much as digits as its factorization.

1669693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2686.

The product of its digits is 52488, while the sum is 40.

The square root of 1669693 is about 1292.1660110063. The cubic root of 1669693 is about 118.6348290566.

Subtracting 1669693 from its reverse (3969661), we obtain a cube (2299968 = 132³).

The spelling of 1669693 in words is "one million, six hundred sixty-nine thousand, six hundred ninety-three".