266813161 has 2 divisors, whose sum is σ = 266813162. Its totient is φ = 266813160.

The previous prime is 266813159. The next prime is 266813203. The reversal of 266813161 is 161318662.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 238393600 + 28419561 = 15440^2 + 5331^2 .

It is a cyclic number.

It is not a de Polignac number, because 266813161 - 2¹ = 266813159 is a prime.

Together with 266813159, it forms a pair of twin primes.

It is equal to p_14547274 and since 266813161 and 14547274 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (266813111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133406580 + 133406581.

It is an arithmetic number, because the mean of its divisors is an integer number (133406581).

Almost surely, 2^266813161 is an apocalyptic number.

It is an amenable number.

266813161 is a deficient number, since it is larger than the sum of its proper divisors (1).

266813161 is an equidigital number, since it uses as much as digits as its factorization.

266813161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 34.

The square root of 266813161 is about 16334.4164572843. The cubic root of 266813161 is about 643.7774337635. Note that the first 3 decimals are identical.

The spelling of 266813161 in words is "two hundred sixty-six million, eight hundred thirteen thousand, one hundred sixty-one".