225621421 has 8 divisors (see below), whose sum is σ = 243550080. Its totient is φ = 208369392.

The previous prime is 225621419. The next prime is 225621437. The reversal of 225621421 is 124126522.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 225621421 - 2¹ = 225621419 is a prime.

It is a super-2 number, since 2×225621421² = 101810051228118482, 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 (225621821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 168465 + ... + 169798.

It is an arithmetic number, because the mean of its divisors is an integer number (30443760).

Almost surely, 2^225621421 is an apocalyptic number.

It is an amenable number.

225621421 is a deficient number, since it is larger than the sum of its proper divisors (17928659).

225621421 is a wasteful number, since it uses less digits than its factorization.

225621421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338315.

The product of its digits is 1920, while the sum is 25.

The square root of 225621421 is about 15020.6997506774. The cubic root of 225621421 is about 608.7796267838.

Adding to 225621421 its reverse (124126522), we get a palindrome (349747943).

The spelling of 225621421 in words is "two hundred twenty-five million, six hundred twenty-one thousand, four hundred twenty-one".