243265961 has 4 divisors (see below), whose sum is σ = 243309252. Its totient is φ = 243222672.

The previous prime is 243265943. The next prime is 243265973. The reversal of 243265961 is 169562342.

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 37515625 + 205750336 = 6125^2 + 14344^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243265961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (243265901) 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 3 ways as a sum of consecutive naturals, for example, 11690 + ... + 24963.

It is an arithmetic number, because the mean of its divisors is an integer number (60827313).

Almost surely, 2^243265961 is an apocalyptic number.

It is an amenable number.

243265961 is a deficient number, since it is larger than the sum of its proper divisors (43291).

243265961 is an equidigital number, since it uses as much as digits as its factorization.

243265961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43290.

The product of its digits is 77760, while the sum is 38.

The square root of 243265961 is about 15596.9856382572. The cubic root of 243265961 is about 624.2527269422.

The spelling of 243265961 in words is "two hundred forty-three million, two hundred sixty-five thousand, nine hundred sixty-one".