225645421 has 4 divisors (see below), whose sum is σ = 225864892. Its totient is φ = 225425952.

The previous prime is 225645419. The next prime is 225645517. The reversal of 225645421 is 124546522.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 201498025 + 24147396 = 14195^2 + 4914^2 .

It is a cyclic number.

It is not a de Polignac number, because 225645421 - 2¹ = 225645419 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 (225640421) 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, 108186 + ... + 110251.

It is an arithmetic number, because the mean of its divisors is an integer number (56466223).

Almost surely, 2^225645421 is an apocalyptic number.

It is an amenable number.

225645421 is a deficient number, since it is larger than the sum of its proper divisors (219471).

225645421 is a wasteful number, since it uses less digits than its factorization.

225645421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219470.

The product of its digits is 19200, while the sum is 31.

The square root of 225645421 is about 15021.4986269679. The cubic root of 225645421 is about 608.8012118989.

The spelling of 225645421 in words is "two hundred twenty-five million, six hundred forty-five thousand, four hundred twenty-one".