225421 has 4 divisors (see below), whose sum is σ = 257632. Its totient is φ = 193212.

The previous prime is 225383. The next prime is 225427. The reversal of 225421 is 124522.

225421 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 225421 - 2⁹ = 224909 is a prime.

It is a Duffinian number.

225421 is a lucky number.

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 225395 and 225404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225427) 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, 16095 + ... + 16108.

It is an arithmetic number, because the mean of its divisors is an integer number (64408).

2²²⁵⁴²¹ is an apocalyptic number.

It is an amenable number.

225421 is a deficient number, since it is larger than the sum of its proper divisors (32211).

225421 is an equidigital number, since it uses as much as digits as its factorization.

225421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32210.

The product of its digits is 160, while the sum is 16.

The square root of 225421 is about 474.7852145971. The cubic root of 225421 is about 60.8599312393.

Adding to 225421 its reverse (124522), we get a palindrome (349943).

It can be divided in two parts, 225 and 421, that added together give a palindrome (646).

The spelling of 225421 in words is "two hundred twenty-five thousand, four hundred twenty-one".