225666421 has 8 divisors (see below), whose sum is σ = 232206264. Its totient is φ = 219211200.

The previous prime is 225666407. The next prime is 225666437. The reversal of 225666421 is 124666522.

It can be written as a sum of positive squares in 4 ways, for example, as 79014321 + 146652100 = 8889^2 + 12110^2 .

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 225666421 - 2¹⁹ = 225142133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225666121) 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, 15726 + ... + 26431.

It is an arithmetic number, because the mean of its divisors is an integer number (29025783).

Almost surely, 2^225666421 is an apocalyptic number.

It is an amenable number.

225666421 is a deficient number, since it is larger than the sum of its proper divisors (6539843).

225666421 is a wasteful number, since it uses less digits than its factorization.

225666421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42311.

The product of its digits is 34560, while the sum is 34.

The square root of 225666421 is about 15022.1976088720. The cubic root of 225666421 is about 608.8200976191.

The spelling of 225666421 in words is "two hundred twenty-five million, six hundred sixty-six thousand, four hundred twenty-one".