266440 has 16 divisors (see below), whose sum is σ = 599580. Its totient is φ = 106560.

The previous prime is 266417. The next prime is 266447. The reversal of 266440 is 44662.

It can be written as a sum of positive squares in 2 ways, for example, as 256036 + 10404 = 506^2 + 102^2 .

It is a d-powerful number, because it can be written as 2⁷ + 6² + 4⁶ + 6² + 4⁹ + 0 .

It is not an unprimeable number, because it can be changed into a prime (266447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3291 + ... + 3370.

2²⁶⁶⁴⁴⁰ is an apocalyptic number.

266440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

266440 is an abundant number, since it is smaller than the sum of its proper divisors (333140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

266440 is a wasteful number, since it uses less digits than its factorization.

266440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6672 (or 6668 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 266440 is about 516.1782637810. The cubic root of 266440 is about 64.3477167824.

It can be divided in two parts, 2664 and 40, that added together give a square (2704 = 52²).

The spelling of 266440 in words is "two hundred sixty-six thousand, four hundred forty".