243124421 has 4 divisors (see below), whose sum is σ = 253695072. Its totient is φ = 232553772.

The previous prime is 243124417. The next prime is 243124439. The reversal of 243124421 is 124421342.

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 an emirpimes, since its reverse is a distinct semiprime: 124421342 = 2 ⋅62210671.

It is a cyclic number.

It is not a de Polignac number, because 243124421 - 2² = 243124417 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 10570627 = 243124421 / (2 + 4 + 3 + 1 + 2 + 4 + 4 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243124411) 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, 5285291 + ... + 5285336.

It is an arithmetic number, because the mean of its divisors is an integer number (63423768).

Almost surely, 2^243124421 is an apocalyptic number.

It is an amenable number.

243124421 is a deficient number, since it is larger than the sum of its proper divisors (10570651).

243124421 is a wasteful number, since it uses less digits than its factorization.

243124421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10570650.

The product of its digits is 1536, while the sum is 23.

The square root of 243124421 is about 15592.4475628427. The cubic root of 243124421 is about 624.1316333150.

Adding to 243124421 its reverse (124421342), we get a palindrome (367545763).

The spelling of 243124421 in words is "two hundred forty-three million, one hundred twenty-four thousand, four hundred twenty-one".