666049 has 4 divisors (see below), whose sum is σ = 674560. Its totient is φ = 657540.

The previous prime is 666041. The next prime is 666067. The reversal of 666049 is 940666.

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, and also an emirpimes, since its reverse is a distinct semiprime: 940666 = 2 ⋅470333.

It is a cyclic number.

It is not a de Polignac number, because 666049 - 2³ = 666041 is a prime.

It is a Duffinian number.

666049 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 666049.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4137 + ... + 4294.

It is an arithmetic number, because the mean of its divisors is an integer number (168640).

2⁶⁶⁶⁰⁴⁹ is an apocalyptic number.

It is an amenable number.

666049 is a deficient number, since it is larger than the sum of its proper divisors (8511).

666049 is an equidigital number, since it uses as much as digits as its factorization.

666049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8510.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 666049 is about 816.1182512357. The cubic root of 666049 is about 87.3310590606.

The spelling of 666049 in words is "six hundred sixty-six thousand, forty-nine".