225661643 has 8 divisors (see below), whose sum is σ = 229480416. Its totient is φ = 221860800.

The previous prime is 225661637. The next prime is 225661661. The reversal of 225661643 is 346166522.

It is a happy number.

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

It is not a de Polignac number, because 225661643 - 2¹⁰ = 225660619 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (225661633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22223 + ... + 30743.

It is an arithmetic number, because the mean of its divisors is an integer number (28685052).

Almost surely, 2^225661643 is an apocalyptic number.

225661643 is a deficient number, since it is larger than the sum of its proper divisors (3818773).

225661643 is an equidigital number, since it uses as much as digits as its factorization.

225661643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8965.

The product of its digits is 51840, while the sum is 35.

The square root of 225661643 is about 15022.0385767046. The cubic root of 225661643 is about 608.8158007711.

It can be divided in two parts, 22 and 5661643, that added together give a palindrome (5661665).

The spelling of 225661643 in words is "two hundred twenty-five million, six hundred sixty-one thousand, six hundred forty-three".