266645 has 8 divisors (see below), whose sum is σ = 338904. Its totient is φ = 200704.

The previous prime is 266641. The next prime is 266647. The reversal of 266645 is 546662.

It can be written as a sum of positive squares in 4 ways, for example, as 148996 + 117649 = 386^2 + 343^2 .

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

It is a 6-Lehmer number, since φ(266645) divides (266645-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 266645 - 2² = 266641 is a prime.

It is a d-powerful number, because it can be written as 2³ + 6² + 6² + 6⁴ + 4⁹ + 5⁵ .

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1484 + ... + 1653.

It is an arithmetic number, because the mean of its divisors is an integer number (42363).

2²⁶⁶⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

266645 is a deficient number, since it is larger than the sum of its proper divisors (72259).

266645 is a wasteful number, since it uses less digits than its factorization.

266645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3159.

The product of its digits is 8640, while the sum is 29.

The square root of 266645 is about 516.3768004084. The cubic root of 266645 is about 64.3642156818.

The spelling of 266645 in words is "two hundred sixty-six thousand, six hundred forty-five".