266856905 has 32 divisors (see below), whose sum is σ = 396990720. Its totient is φ = 168007680.

The previous prime is 266856901. The next prime is 266856907. The reversal of 266856905 is 509658662.

It is not a de Polignac number, because 266856905 - 2² = 266856901 is a prime.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 266856905.

It is not an unprimeable number, because it can be changed into a prime (266856901) 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 in 31 ways as a sum of consecutive naturals, for example, 18926 + ... + 29864.

It is an arithmetic number, because the mean of its divisors is an integer number (12405960).

Almost surely, 2^266856905 is an apocalyptic number.

It is an amenable number.

266856905 is a deficient number, since it is larger than the sum of its proper divisors (130133815).

266856905 is a wasteful number, since it uses less digits than its factorization.

266856905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11009.

The product of its (nonzero) digits is 777600, while the sum is 47.

The square root of 266856905 is about 16335.7554156519. The cubic root of 266856905 is about 643.8126142634.

The spelling of 266856905 in words is "two hundred sixty-six million, eight hundred fifty-six thousand, nine hundred five".