266165489 has 2 divisors, whose sum is σ = 266165490. Its totient is φ = 266165488.

The previous prime is 266165437. The next prime is 266165491. The reversal of 266165489 is 984561662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 245079025 + 21086464 = 15655^2 + 4592^2 .

It is a cyclic number.

It is not a de Polignac number, because 266165489 - 2⁸ = 266165233 is a prime.

Together with 266165491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (266165429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133082744 + 133082745.

It is an arithmetic number, because the mean of its divisors is an integer number (133082745).

Almost surely, 2^266165489 is an apocalyptic number.

It is an amenable number.

266165489 is a deficient number, since it is larger than the sum of its proper divisors (1).

266165489 is an equidigital number, since it uses as much as digits as its factorization.

266165489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 622080, while the sum is 47.

The square root of 266165489 is about 16314.5790322644. The cubic root of 266165489 is about 643.2561020935.

The spelling of 266165489 in words is "two hundred sixty-six million, one hundred sixty-five thousand, four hundred eighty-nine".