266566 has 4 divisors (see below), whose sum is σ = 399852. Its totient is φ = 133282.

The previous prime is 266549. The next prime is 266587. The reversal of 266566 is 665662.

It is a semiprime because it is the product of two primes.

It is a nialpdrome in base 13.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 266566.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66640 + ... + 66643.

It is an arithmetic number, because the mean of its divisors is an integer number (99963).

2²⁶⁶⁵⁶⁶ is an apocalyptic number.

266566 is a deficient number, since it is larger than the sum of its proper divisors (133286).

266566 is a wasteful number, since it uses less digits than its factorization.

266566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133285.

The product of its digits is 12960, while the sum is 31.

The square root of 266566 is about 516.3003002130. The cubic root of 266566 is about 64.3578585712.

It can be divided in two parts, 26656 and 6, that added together give a palindrome (26662).

The spelling of 266566 in words is "two hundred sixty-six thousand, five hundred sixty-six".