266655565 has 12 divisors (see below), whose sum is σ = 351721692. Its totient is φ = 193930880.

The previous prime is 266655553. The next prime is 266655589. The reversal of 266655565 is 565556662.

It can be written as a sum of positive squares in 2 ways, for example, as 78801129 + 187854436 = 8877^2 + 13706^2 .

It is not a de Polignac number, because 266655565 - 2⁵ = 266655533 is a prime.

It is a super-2 number, since 2×266655565² = 142210380690938450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 219772 + ... + 220981.

It is an arithmetic number, because the mean of its divisors is an integer number (29310141).

Almost surely, 2^266655565 is an apocalyptic number.

It is an amenable number.

266655565 is a deficient number, since it is larger than the sum of its proper divisors (85066127).

266655565 is a wasteful number, since it uses less digits than its factorization.

266655565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440780 (or 440769 counting only the distinct ones).

The product of its digits is 1620000, while the sum is 46.

The square root of 266655565 is about 16329.5916972838. The cubic root of 266655565 is about 643.6506574954.

The spelling of 266655565 in words is "two hundred sixty-six million, six hundred fifty-five thousand, five hundred sixty-five".