1665993 has 8 divisors (see below), whose sum is σ = 2538688. Its totient is φ = 951984.

The previous prime is 1665973. The next prime is 1665997. The reversal of 1665993 is 3995661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1665993 - 2⁶ = 1665929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1665997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39646 + ... + 39687.

It is an arithmetic number, because the mean of its divisors is an integer number (317336).

2^1665993 is an apocalyptic number.

It is an amenable number.

1665993 is a deficient number, since it is larger than the sum of its proper divisors (872695).

1665993 is an equidigital number, since it uses as much as digits as its factorization.

1665993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79343.

The product of its digits is 43740, while the sum is 39.

The square root of 1665993 is about 1290.7335123874. The cubic root of 1665993 is about 118.5471335939.

The spelling of 1665993 in words is "one million, six hundred sixty-five thousand, nine hundred ninety-three".