266891 has 2 divisors, whose sum is σ = 266892. Its totient is φ = 266890.

The previous prime is 266867. The next prime is 266897. The reversal of 266891 is 198662.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266891 is a prime.

It is not a weakly prime, because it can be changed into another prime (266897) 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 as a sum of consecutive naturals, namely, 133445 + 133446.

It is an arithmetic number, because the mean of its divisors is an integer number (133446).

2²⁶⁶⁸⁹¹ is an apocalyptic number.

266891 is a deficient number, since it is larger than the sum of its proper divisors (1).

266891 is an equidigital number, since it uses as much as digits as its factorization.

266891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 32.

The square root of 266891 is about 516.6149436476. The cubic root of 266891 is about 64.3840032024.

The spelling of 266891 in words is "two hundred sixty-six thousand, eight hundred ninety-one".