225731665 has 4 divisors (see below), whose sum is σ = 270878004. Its totient is φ = 180585328.

The previous prime is 225731657. The next prime is 225731669. The reversal of 225731665 is 566137522.

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 28132416 + 197599249 = 5304^2 + 14057^2 .

It is a cyclic number.

It is not a de Polignac number, because 225731665 - 2³ = 225731657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (225731669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22573162 + ... + 22573171.

It is an arithmetic number, because the mean of its divisors is an integer number (67719501).

Almost surely, 2^225731665 is an apocalyptic number.

It is an amenable number.

225731665 is a deficient number, since it is larger than the sum of its proper divisors (45146339).

225731665 is an equidigital number, since it uses as much as digits as its factorization.

225731665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45146338.

The product of its digits is 75600, while the sum is 37.

The square root of 225731665 is about 15024.3690383324. The cubic root of 225731665 is about 608.8787653801.

The spelling of 225731665 in words is "two hundred twenty-five million, seven hundred thirty-one thousand, six hundred sixty-five".