266240621 has 4 divisors (see below), whose sum is σ = 281901852. Its totient is φ = 250579392.

The previous prime is 266240609. The next prime is 266240629. The reversal of 266240621 is 126042662.

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 248692900 + 17547721 = 15770^2 + 4189^2 .

It is a cyclic number.

It is not a de Polignac number, because 266240621 - 2¹⁴ = 266224237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266240629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7830590 + ... + 7830623.

It is an arithmetic number, because the mean of its divisors is an integer number (70475463).

Almost surely, 2^266240621 is an apocalyptic number.

It is an amenable number.

266240621 is a deficient number, since it is larger than the sum of its proper divisors (15661231).

266240621 is a wasteful number, since it uses less digits than its factorization.

266240621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15661230.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 266240621 is about 16316.8814728796. The cubic root of 266240621 is about 643.3166215483.

The spelling of 266240621 in words is "two hundred sixty-six million, two hundred forty thousand, six hundred twenty-one".