243138453 has 4 divisors (see below), whose sum is σ = 324184608. Its totient is φ = 162092300.

The previous prime is 243138443. The next prime is 243138463. The reversal of 243138453 is 354831342.

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.

It is an interprime number because it is at equal distance from previous prime (243138443) and next prime (243138463).

It is a cyclic number.

It is not a de Polignac number, because 243138453 - 2⁸ = 243138197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243138443) 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, 40523073 + ... + 40523078.

It is an arithmetic number, because the mean of its divisors is an integer number (81046152).

Almost surely, 2^243138453 is an apocalyptic number.

It is an amenable number.

243138453 is a deficient number, since it is larger than the sum of its proper divisors (81046155).

243138453 is an equidigital number, since it uses as much as digits as its factorization.

243138453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81046154.

The product of its digits is 34560, while the sum is 33.

The square root of 243138453 is about 15592.8975177803. The cubic root of 243138453 is about 624.1436403997.

Adding to 243138453 its reverse (354831342), we get a palindrome (597969795).

The spelling of 243138453 in words is "two hundred forty-three million, one hundred thirty-eight thousand, four hundred fifty-three".