225391 has 4 divisors (see below), whose sum is σ = 226512. Its totient is φ = 224272.

The previous prime is 225383. The next prime is 225427. The reversal of 225391 is 193522.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 225391 - 2³ = 225383 is a prime.

It is a super-2 number, since 2×225391² = 101602205762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166 + ... + 691.

It is an arithmetic number, because the mean of its divisors is an integer number (56628).

2²²⁵³⁹¹ is an apocalyptic number.

225391 is a deficient number, since it is larger than the sum of its proper divisors (1121).

225391 is an equidigital number, since it uses as much as digits as its factorization.

225391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1120.

The product of its digits is 540, while the sum is 22.

The square root of 225391 is about 474.7536203127. The cubic root of 225391 is about 60.8572312853.

It can be divided in two parts, 225 and 391, that added together give a palindrome (616).

The spelling of 225391 in words is "two hundred twenty-five thousand, three hundred ninety-one".