243420253 has 4 divisors (see below), whose sum is σ = 247546080. Its totient is φ = 239294428.

The previous prime is 243420227. The next prime is 243420283. The reversal of 243420253 is 352024342.

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 a cyclic number.

It is not a de Polignac number, because 243420253 - 2¹³ = 243412061 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 (243420223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2062825 + ... + 2062942.

It is an arithmetic number, because the mean of its divisors is an integer number (61886520).

Almost surely, 2^243420253 is an apocalyptic number.

It is an amenable number.

243420253 is a deficient number, since it is larger than the sum of its proper divisors (4125827).

243420253 is an equidigital number, since it uses as much as digits as its factorization.

243420253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4125826.

The product of its (nonzero) digits is 5760, while the sum is 25.

The square root of 243420253 is about 15601.9310663776. The cubic root of 243420253 is about 624.3846769629.

Adding to 243420253 its reverse (352024342), we get a palindrome (595444595).

The spelling of 243420253 in words is "two hundred forty-three million, four hundred twenty thousand, two hundred fifty-three".