266855189 has 2 divisors, whose sum is σ = 266855190. Its totient is φ = 266855188.

The previous prime is 266855107. The next prime is 266855191. The reversal of 266855189 is 981558662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 225510289 + 41344900 = 15017^2 + 6430^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266855189 is a prime.

Together with 266855191, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (266855089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133427594 + 133427595.

It is an arithmetic number, because the mean of its divisors is an integer number (133427595).

Almost surely, 2^266855189 is an apocalyptic number.

It is an amenable number.

266855189 is a deficient number, since it is larger than the sum of its proper divisors (1).

266855189 is an equidigital number, since it uses as much as digits as its factorization.

266855189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1036800, while the sum is 50.

The square root of 266855189 is about 16335.7028927439. The cubic root of 266855189 is about 643.8112342669.

The spelling of 266855189 in words is "two hundred sixty-six million, eight hundred fifty-five thousand, one hundred eighty-nine".