225664 has 32 divisors (see below), whose sum is σ = 471240. Its totient is φ = 107520.

The previous prime is 225637. The next prime is 225671. The reversal of 225664 is 466522.

It is a tau number, because it is divible by the number of its divisors (32).

It is a plaindrome in base 11.

It is a congruent number.

It is an unprimeable number.

225664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5227 + ... + 5269.

2²²⁵⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 225664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235620).

225664 is an abundant number, since it is smaller than the sum of its proper divisors (245576).

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

225664 is an equidigital number, since it uses as much as digits as its factorization.

225664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98 (or 86 counting only the distinct ones).

The product of its digits is 2880, while the sum is 25.

The square root of 225664 is about 475.0410508577. The cubic root of 225664 is about 60.8817920425.

Subtracting from 225664 its product of digits (2880), we obtain a square (222784 = 472²).

The spelling of 225664 in words is "two hundred twenty-five thousand, six hundred sixty-four".