266745665 has 4 divisors (see below), whose sum is σ = 320094804. Its totient is φ = 213396528.

The previous prime is 266745659. The next prime is 266745679. The reversal of 266745665 is 566547662.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 208253761 + 58491904 = 14431^2 + 7648^2 .

It is a cyclic number.

It is not a de Polignac number, because 266745665 - 2¹² = 266741569 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26674562 + ... + 26674571.

It is an arithmetic number, because the mean of its divisors is an integer number (80023701).

Almost surely, 2^266745665 is an apocalyptic number.

It is an amenable number.

266745665 is a deficient number, since it is larger than the sum of its proper divisors (53349139).

266745665 is an equidigital number, since it uses as much as digits as its factorization.

266745665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53349138.

The product of its digits is 1814400, while the sum is 47.

The square root of 266745665 is about 16332.3502595309. The cubic root of 266745665 is about 643.7231435052.

The spelling of 266745665 in words is "two hundred sixty-six million, seven hundred forty-five thousand, six hundred sixty-five".