266565 has 16 divisors (see below), whose sum is σ = 459648. Its totient is φ = 131136.

The previous prime is 266549. The next prime is 266587. The reversal of 266565 is 565662.

266565 = T₁₃₀ + T₁₃₁ + ... + T₁₅₅.

It is not a de Polignac number, because 266565 - 2⁴ = 266549 is a prime.

It is a nialpdrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 489 + ... + 878.

It is an arithmetic number, because the mean of its divisors is an integer number (28728).

266565 is a Friedman number, since it can be written as 65*(5+(6-2)^6), using all its digits and the basic arithmetic operations.

2²⁶⁶⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

266565 is a deficient number, since it is larger than the sum of its proper divisors (193083).

266565 is a wasteful number, since it uses less digits than its factorization.

266565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1388.

The product of its digits is 10800, while the sum is 30.

The square root of 266565 is about 516.2993317834. The cubic root of 266565 is about 64.3577780933.

The spelling of 266565 in words is "two hundred sixty-six thousand, five hundred sixty-five".