225681 has 4 divisors (see below), whose sum is σ = 300912. Its totient is φ = 150452.

The previous prime is 225671. The next prime is 225683. The reversal of 225681 is 186522.

225681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 225681 - 2¹¹ = 223633 is a prime.

It is a super-2 number, since 2×225681² = 101863827522, which contains 22 as substring.

It is a D-number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 225681.

It is not an unprimeable number, because it can be changed into a prime (225683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37611 + ... + 37616.

It is an arithmetic number, because the mean of its divisors is an integer number (75228).

2²²⁵⁶⁸¹ is an apocalyptic number.

It is an amenable number.

225681 is a deficient number, since it is larger than the sum of its proper divisors (75231).

225681 is an equidigital number, since it uses as much as digits as its factorization.

225681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75230.

The product of its digits is 960, while the sum is 24.

The square root of 225681 is about 475.0589437112. The cubic root of 225681 is about 60.8833208116.

The spelling of 225681 in words is "two hundred twenty-five thousand, six hundred eighty-one".