243425521 has 4 divisors (see below), whose sum is σ = 243457344. Its totient is φ = 243393700.

The previous prime is 243425503. The next prime is 243425527. The reversal of 243425521 is 125524342.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 243425521 - 2⁹ = 243425009 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 243425521.

It is not an unprimeable number, because it can be changed into a prime (243425527) 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, 3276 + ... + 22306.

It is an arithmetic number, because the mean of its divisors is an integer number (60864336).

Almost surely, 2^243425521 is an apocalyptic number.

It is an amenable number.

243425521 is a deficient number, since it is larger than the sum of its proper divisors (31823).

243425521 is a wasteful number, since it uses less digits than its factorization.

243425521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31822.

The product of its digits is 9600, while the sum is 28.

The square root of 243425521 is about 15602.0998907198. The cubic root of 243425521 is about 624.3891811550.

Adding to 243425521 its reverse (125524342), we get a palindrome (368949863).

The spelling of 243425521 in words is "two hundred forty-three million, four hundred twenty-five thousand, five hundred twenty-one".